Download 852Plus user manual Rev-2-32

Series 852Plus V32
Transformer Temperature
Monitor
(WTI, OTI & Quadrature Booster Over Temperature Protection
With Auto Cool Mode)
USER MANUAL
(Issue number noted on page 3)
Ashridge Engineering Limited
West View Road
Okehampton
Devon
EX20 1NF
UK
Tel : +44 (0) 1837 53381
Fax : +44 (0) 1837 55022
Email : [email protected]
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Subject to change without notification. Whilst every effort has been taken to ensure the contents of this document are accurate no responsibility can be accepted for any errors contained within
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Ashridge Engineering Ltd
Specification:
3 wire PT100 input: +/- 1°C @ 20°C, PT100 input to Analogue output: +/- 2°C @ 20°C
Analogue output: 0-10, 0-20 & 4-20mA (User selectable). Maximum loop resistance 975Ω .
CT input: 0-10Amp (User defined between 0-0.5 and 0-10) +/- 2% @ 20°C, (CT = 0.03VA, 1:1000)
Overload capability: 75A for 3 seconds
Relay outputs: Watchdog and Cool Fail plus 4 off user adjustable for Pump, Fan, Alarm and Trip
all with N/O or N/C volt free contacts (user selectable by links).
Relay rating: 5A Non inductive (Breaking: 110Vdc/0.4A).
Environmental: Operating temperature range: 0 to 55°C and 0-95% RH Non condensating
Wall mounted enclosure to IP65, Panel mounted enclosure to IP55.
Power supply: Universal input, 85-265 Volts ac, 90-260 Volts dc, power consumption less than
6VA.
EMC:
Meets the intent of Directive 89/336
And LVD 73/23/ECC
IEC255-5, EN55022, EN50081-1, EN55011, EN6100-4-2, EN6100-4-3, EN6100-4-4, EN6100-4-5,
EN6100-4-6, EN6100-4-11, EN6100-4-12.
Also conforms to the following: NGTS (UK National Grid Technical Specification) 2.13, Issue 3
for EMC and Environmental, NGTS 3.3.8 Issue 1 for EMC and Environmental (Confirmation of
approval number NGTS by mid October 1999)
Ashridge Engineering Ltd
West View Road
Okehampton
Devon. UK
EX20 1NF
Tel: +44 (0) 1837 53381
Fax: +44 (0) 1837 55022
Email: [email protected]
DISCLAIMER
ASHRIDGE ENGINEERING LIMITED RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY
PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. ASHRIDGE ENGINEERING LIMITED DOES NOT
ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN.
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Ashridge Engineering Ltd
User Manual
Series 852Plus
Issue V32f (121203)
V32f: This incorporates Auto Cool feature, which allows the user to set the 852Plus to exercise the cooling system at
regular intervals. Other changes: a) allow the user to select 1, 2 or 3 gradients b) Fans and Pumps are initiated for
PT100 failure c) Cool Fail feedback types now incorporates ‘none’ where no digital or CT types are available. For
Inversion of Fan and Pump relays, see 2.13 for details.
1. Description
1.1 Standard mode & Hot Spot formula (IEC354)
1.1.1
Step mode (Initiated under Settings)
1.1.2
Watchdog
1.1.3
Cool Fail & Pump and Fan monitoring
2. Setting up 852Plus
2.1 Key sequences
2.2 Setup routine
2.3 Adjusting display brightness
2.4 Adjusting the relay setpoints
2.5 Adjusting the Settings
2.6 Auto Cool mode
2.7 Teach mode
2.8 Calibration
2.9 Error and Alarm messages
2.9.1
Entering Modbus parameters
2.10.1 Modbus Holding register
2.10.2 Modbus (Coil status)
2.10.3 Modbus (Input register)
2.10.4 Modbus (Input status)
2.10.5 Modbus connection example
2.11 Returning the 852 to default settings
2.12 Relay Test Mode
2.13 Password list
3.0
Electrical Installation
3.0.1
Mechanical Installation
3.1.1
Wiring Diagram
3.2.1
CT input conditioning & Relay O/P link arrangements (Wall mounted version)
3.2.3
Selection of Relay output types
3.2.4
Terminal arrangement (Panel mounted version)
3.2.5
Selection of ‘Digital input’ type (See 3.2.1 for link assignment details)
3.2.6
Selection of Relay output types
3.3.1
Dimensions (DIN 144 version)
3.3.2
Dimensions (Wall mounted version)4. Typical displays from 852Plus
4. Typical displays from 852Plus
5. 852Plus Application note 1
6. 852Plus Application note 2
7. Application note 3:
8. Commissioning
9. Series 852Plus Record Sheet
10. Notes :
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1.
Description
The Transformer Temperature Monitor (including Winding Temperature Indicator functions) is an intelligent microprocessor
controlled Digital Indicator with inputs for CT, PT100 temperature probe, Pump and Fan confirmation signals and Pump & Fan
remote activation signal. Outputs available are Analogue output(s), RS485 (Modbus) and 6 off volt free relay contacts (Normally
open or normally closed by link selection). The unit is user configurable via an integral keypad and manufacturer defined passwords
for security of data. All stored data is non-volatile flash with the exception of the time/date function which uses a ‘Supercap’ to
maintain the time and date for a period of some 2 weeks without power, after which time the unit would require the time/date
resetting by the user.
Isolation rationale
To meet the general requirements of clause (5.5.6.13 of NGC 2.13, issue 3 (Dielectric and insulation resistance between inputs and
outputs) the instrument has been designed with high integrity input and power supply sections.
Isolation of 2000 volts is maintained between power supply and input section, power supply and output section and input
section to output section. Relay isolation is a minimum of 2000 volts between contacts and all circuitry thus ensuring a high
level of integrity for the control and protection of Transformers. The 852Plus measures the oil temperature using a 3 wire
class B PT100, the CT input has a 0-10 Amp ac input, there are 6 relay outputs, 4 of which have user adjustable parameters
(via the necessary passwords). Analogue and Modbus ports provide outputs to other monitoring equipment.
1.1
Standard mode & Hot Spot formula (IEC354)
The 852Plus measures the oil temperature and CT current and displays the ‘Hot spot’ corrected temperature on a 6 digit
display using the IEC354 formula: θ Hot Spot = θ top-oil + H gr Ky, (Where H = Manufacturers factor, usually due to
the placement of PT100 sensor, Where gr = Manufacturers winding gradient, normally entered as Natural Winding
Gradient (ONAN) and Forced Winding Gradient (OFAF), Where K = CT input as Load factor, Where y =
Transformer dependant factor)
Push buttons are provided for setting up and commissioning the unit via passwords. The push buttons
are also used to display and reset the ‘peak temperature’ since the last reset, the ‘Top oil’ temperature
and the CT current in Amps. An extra function, using the shift and CT push buttons allows the Pump
and Fan running current to be observed when in that mode.
Relays are used to provide volt free contacts, at user definable temperatures for operation of Pumps,
Fans, Alarm and Trip. The Watchdog and Cool fail relays are not definable by the user. Analogue and
Modbus ports provide interfaces to other monitoring equipment.
Inputs are provided to allow the Pump and Fan to be monitored for correct operation. A separate input
allows the Pump and Fan to remotely operated.
1.1.1 Step mode (Initiated under Settings)
Used where a sudden large step change in CT current could cause the oil to overheat before the
temperature rises sufficiently to switch on the Pump at the normal pre-set temperature. Such instances
are Combined Power and Heat power stations at switch on, also where electric trains can cause very
high currents to be drawn for short periods.
In this mode a level for the CT step change to operate is set and a time period for the Pump to remain
operational after the initialisation of the pump. To enable this function go to setup menu, the parameter
required toggles between onAn and SteP, select step, followed by the threshold current, followed by the
time for the Pump to remain energised, after the step change before returning to normal operation.
1.1.2 Watchdog
The watchdog relay has volt free contacts with link selectable outputs of normally open or normally
closed, i.e. Where closed contacts are required to indicate a healthy system use normally open contacts
as healthy system=energised relay. The watchdog relay de-energises in the event of:
a) PT100 failure or PT100 wiring fault (and automatically energises the Fan & Pump relays)
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b) Power failure.
c) Internal component failure (and automatically energises the Fan & Pump relays).
In the event of a watchdog failure, for a PT100 or internal fault the Fan & Pump relays energise, this
allows ‘fail safe’ operation this is especially important where a failure has occurred when the
transformer is operating at an elevated temperature. The analogue output drops to 0mA to indicate a
fault condition. In the event of a power failure the Fan & Pump relays do not energise.
Operation of the watchdog relay will not cause the unit to operate the trip relay.
1.1.3 Cool Fail & Pump and Fan monitoring
A ‘Cool fail’ relay is also incorporated to indicate when a pump or Fan, which has been called for does
not respond. This is achieved in one of 3 ways, the first simply uses a contact closure which is normally
initiated from the pump or fan contactor to provide a feedback to the PP & Common and Fn &
Common inputs. In use this energises ‘Cool-Fail’ relay and provides a volt free contact approximately 2
minutes after the Pump or Fan has been called for but has not responded.
The second method uses an external CT and internal burden resistor to monitor the running current of
both Pump and Fan providing feedback to the PP, Fn & Common inputs. In this instance the 852Plus
monitors the running current of the Pump and Fan and where it is outside parameters set by the user,
this energises the ‘Cool-Fail’ relay and provides a volt free contact approximately 2 minutes after the
Pump or Fan fails to operate correctly.
The third method uses an external CT and external burden resistor to the PP & Common and Fn &
Common inputs, this option allows larger running currents to be monitored than the internal burden
resistor is able to accommodate. When in ‘CT’ mode the Pump & Fan running currents may be
observed by holding down the ‘shift and CT’ key together, the Pump running figure is shown on the left
and the Fan running current on the right.
Common to all three methods is the action of the 852Plus to a ‘failed’ Pump or Fan. Where a Fan has a
‘failed’ input the ‘Cool fail’ relay energises after the pre-set time period. Where the Pump has a ‘failed’
input the ‘Cool fail’ relay is also energised after the pre-set time period, however where the pump has
failed the unit will not allow the ‘Hot spot’ correction to move from the ONAN to the OFAF curve. As
soon as it detects the correct input the ‘Hot spot’ correction will operate normally, via the timer and the
‘Cool fail’ relay will de-energise.
Each of the three methods is set on the main PCB using links provided, H5 (Pump) & H6 (Fan).
Please note: (1) Whether the Pump or Fan is operated manually, the Fan & Pump are operated as a result of
a watchdog failure or the Pump and Fan has been initiated by a Sp input the ‘Cool fail’ system will continue to
operate as described above.
2.
2.1
Setting up 852Plus
Key sequences
Press the enter (Ã) key to go through program loop
Press and hold down the Shift key and (Æ) to reverse through program loop
Press the (ñ) key to raise the value of the flashing digit
Press and hold down the Shift key and the (ò) to lower the value of the flashing digit
Press the (ï) key to move the flashing digit to the left
Press the hold down the Shift key and the (ð) key to move the flashing digit to the right
General Notes:
a)
Where an incorrect password is entered the display drops to dim mode and allows the user to view the
settings without having access to changing them.
b)
With no key movements applied the unit will return to normal operation after approximately 2 minutes.
c)
Hold ‘shift’ & ‘enter’ keys to abort at any time
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2.2
Setup routine
Setting the Time/Date
All stored data is non-volatile flash with the exception of the time/date function which uses a ‘Supercap’ to maintain the
time and date for a period of some 2 weeks without power, after which time the unit would require the time/date
resetting by the user. Hold down Shift and press Enter (Ã) for approx 2 seconds until display reads ready before
releasing the enter key. Now Hold down shift and press ‘Enter’ a second time this allows the user to adjust
time/date. Use up/down left/right keys to edit each value. Press the enter key to move to next value, on
completion press the save key to exit and save.
2.3
Adjusting display brightness
Hold down Shift and press Enter (Ã) for approx 2 seconds (display reads setup ) until display reads ready
before releasing the enter key, display shows bright , use up key to increase brightness or down key (shift+up
keys) to reduce brightness. Press save on completion.
2.4
Adjusting the relay setpoints
Hold down Shift and press Enter (Ã) for approx 2 seconds (display reads setup ) until display reads
ready before releasing the enter key, display shows bright .
Press the enter key again, enter the password 000042 and press enter key
The relay ‘on’ & ‘off’ points can now be adjusted using the list below for reference.
Display with
Display with
Remarks
key pressed
Key released
alarm on 90.0 Alarm relay ‘Switch On’ point in °C (rising temp)
alarm of 85.0 Alarm relay ‘Switch Off’ point in °C (falling temp)
delay sec 3
Alarm relay De-bounce time in seconds (3-60 seconds)
pump on 75.0 Pump relay ‘Switch On’ point in °C (rising temp)
pump on 55.0 Pump relay ‘Switch Off’ point in °C (falling temp)
delay sec 3
Pump relay De-bounce time in seconds(3-60 seconds)
pump on 75.0 Fan relay ‘Switch On’ point in °C (rising temp)
pump on 55.0 Fan relay ‘Switch Off’ point in °C (falling temp)
delay sec 3
Fan relay De-bounce time in seconds(3-60 seconds)
trip on 120.0 Trip1 relay ‘Switch On’ point in °C (rising temp)
trip on 115.0 Trip1relay ‘Switch Off’ point in °C (falling temp)
delay sec 6
Trip1 relay De-bounce time in seconds(6-60 seconds)
Press ‘Save’ to save and exit or press the ‘enter’ key for access to the settings password
2.5
Adjusting the Settings
Hold down Shift and press Enter (Ã) for approx 2 seconds (display reads setup ) until display reads ready
before releasing the enter key, display shows brightPress the enter key again -----0. Enter password 66 to
access Settings parameters
Display with
Display with
Remarks
key pressed
Key released
grad
gr 2 Select the number of gradients required (1, 2 or 3, default 2, this automatically
selects the correct number of parameters for user inputs, default 2 gradient shown for clarity)
onan
c 15.0 ONAN (Natural) Winding Gradient in Degrees C (gr, range 0-200°C)
onanct a 2.500 ONAN current in amps (0.25-5.00 Amps)
onan h h 1.0 See IEC354 (range 1.0 to 1.4) for details see section 1.1, page 2
onan y y 1.6
See IEC354 (range 1.5 to 2.2) for details see section 1.1, page 2
ofaf
c 16.0 OFAF (Forced) Winding Gradient in Degrees C (gr, 0-200°C)
ofafct a 5.000 OFAF current in amps (0.5-10.00 Amps)
ofaf h h 1.0 See IEC354 (range 1.0 to 1.4) for details see section 1.1, page 2
ofaf
y
y 1.6
See IEC354 (range 1.5 to 2.2) for details see section 1.1, page 2
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transf 480
Time in seconds, ONAN to OFAF & OFAF to ONAN
t-lag
min 0 0-10 (1 min steps)Exponential timer, simulates thermal lag in transformer coil)
on-st onan-step Toggle using up key (ñ) if 5tEP is chosen the next parameter is
thresh a 2.500
This sets the CT current threshold for the step change (after the CT current
has been higher than the threshold for more than 90 seconds range 1-240)
time
min 90
Time before the Pump returns to local control
rollav av 2
Rolling average filter to reduce display flicker (range 0-10 secs, default 2)
op 1
4-20 0-10 0-20 Analogue o/p 1 follows the Hot Spot corrected temperature
select the output type required using the up key
range 0-200 0-150 30-150
Select the required output range using the up key
(Note this range applies to o/p 1 and o/p 2)
op 2
t-oil ct
Analogue o/p 2 retransmits Top Oil temperature or the CT value
select the output type using the up key
op 2
4-20 0-10 0-20 Select the output type using the up key
type
cotact ct none Toggle between cool fail input types as required using up key (ñ)
dev
10
Plus or minus % of input deviation for ct type cool fail inputs
delay min 2 Time delay before cool fail message appears (2 to 30 Minutes)
2.6
Auto Cool mode
Hold down Shift and press Enter (Ã) for approx 2 seconds (display reads setup ) until display reads ready
before releasing the enter key, display shows brightPress the enter key again -----0. Enter password 141
to access Settings parameters
Display with
key pressed
Display with
Key released
Remarks
Auto C on off
Alarm type 1
intrvl day 7
run
Start hr 10
Start min 0
Select ON or OFF using the up key
Select type 1, 2 or 3 see notes below
Select number of days interval between cooling exercises
min 10 Select run time in minutes, maximum 120 minutes
Enter start time HOUR in 24 hour format
Enter start time MINUTE
Press SAVE to save and exit or Shift plus save to abort and exit
Notes on Alarm types (Type 1, 2 or 3 (default 1):
a. Type 1 (Single stage cool fail alarm), i.e. Normal cool fail mode
b. Type 2 (2 stage cool fail alarm for Fans only), i.e. Where 2 is selected the terms "DFl" and
second line DF2" is added for the Fans (Pumps remains "deV" under password 101 (teach
running currents) these select the alarm deviation and conditions for both the analogue output 2
(to energise external relay) and the normal cool fail relay. When this option has been selected the
analogue output 2 automatically shows "rel 7" under password 66 to indicate that output 2 is no
longer available as an analogue output.
c. Type 3 (2 stage cool fail alarm for both Fans and Pumps), i.e. Where 3 is selected the terms "DFl
" and "DF2" is added for Fans and "DPl " and "DP2" is added for Pumps under password 101
(teach running currents) these select the percentage deviation and conditions for both the
analogue output 2 (to energise external relay) and the standard cool fail relay. When this option
has been selected the analogue output 2 automatically shows "reI 7" under password 66 to
indicate that output 2 is no longer available as an analogue output
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Notes on Auto Cool mode
d. When Auto Cool has been enabled the unit will operate at the first available time following
initiation, followed thereafter at the interval days set.
e. The unit will restart the timing process if there has been an interruption in the power supply
or after any of the settings have been changed and saved.
f. Under password 66 the 2nd analogue output will show the new term "reI 7" when condition
2 or 3 has been selected under password 141, see above. For types 1 and 2 the external relay
shown below will be required, this is a high sensitivity DIN rail mounted relay with c/o
contacts rated at 120vdc 300mA breaking (see specification sheet for full details)
2.7
Teach mode
Hold down Shift and press Enter (Ã) for approx 2 seconds (display reads setup ) until display reads ready
before releasing the enter key, display shows bright Press the enter key again -----0. Enter password 101
to access Teach mode parameters
After entering the password the unit displays the Fan and Pump running currents (The Pump on the left and the
Fan on the right) i.e.
47
48
As far as is practicable the ct turns ratio and burden resistor values should be selected to obtain
each reading in the range of 45 to 75, where initial readings are very much different the turns
ration/burden resistor should be re-selected to bring within 40 to 85 maximum.
When satisfied with the readings press the save key
Dev f
Dev p
Min 2
Select the Fan deviation (expressed as a percentage of reading saved) that will cause the
Cool Fail relay to energise. Press Save to save and continue or enter to continue without saving.
Select the Pump deviation (expressed as a percentage of reading saved) that will cause the
Cool Fail relay to energise. Press Save to save and continue or enter to continue without saving.
Select the number of minutes before the Cool Fail relay energises after the start of the deviation
Press Save to save and continue or enter to continue without saving.
Note: Where the Auto Cool feature has been enabled there will be different parameters shown than indicated
above i.e.:
For Type 2
Select the percentage of Fan 'ct' running current reading before the analogue output 2 applies
20mA to energise the external relay for 'abnormal cooler alarm' (default 10) Note: There is
no screen message to indicate this fault
Select the percentage of Fan 'ct' running current reading before the normal 'Cool Fail' relay
energises to indicate a cool fail alarm condition (default 25) Note: The normal Cool Fail
screen message & relay indicates this fault
Select the number of minutes before the Cool Fail relay energises after the start of the
deviation Press Save to save and continue or enter to continue without saving
DF1
DF2
Nin 2
For Type 3
DF1
DF2
Dp1
Dp2
Nin 2
Select the percentage of Fan 'ct' running current reading before the analogue output 2 applies
20mA to energise the external relay for 'abnormal cooler alarm' (default 10) Note: There is
no screen message to indicate this fault
Select the percentage of Fan 'ct' running current reading before the normal 'Cool Fail' relay
energises to indicate a cool fail alarm condition (default 25) Note: The normal Cool Fail
screen message & relay indicates this fault
Select the percentage of Pump 'ct' running current reading before the analogue output 2
applies 20mA to energise the external relay for 'abnormal cooler alarm' (default 10) Note:
There is no screen message to indicate this fault
Select the percentage of Pump 'ct' running current reading before the normal 'Cool Fail'
relay energises to indicate a cool fail alarm condition (default 25) Note: The normal Cool
Fail screen message & relay indicates this fault
Select the number of minutes before the Cool Fail relay energises after the start of the
deviation Press Save to save and continue or enter to continue without saving
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Type 2 Alarm type
This offers stage one warning of partial failure and operates an external DIN rail mounted relay, which is
operated from the second analogue output (Note: There is no screen message to indicate this fault).
Stage two uses the normal Cool Fail system to generate alarm and control of the cooling gradients.
Connections:
1
2
The externally mounted DIN rail relay (details below) is connected to analogue output terminals
(852 Terminal 23 to relay Al, 852 terrninal25 to relay A2)
All other connections remain the same as previous
2.8
Calibration
cALl6
-----0
0 c
200 c
Ct1 5A
20nA
20nA
2.9
Calibration, factory access only
Raw value
Apply correct input & press up key then enter key to load new value
or enter key to skip
Raw value
Apply correct input & press up key then enter key to load new value
or enter key to skip
Raw value
Apply correct input & press up key then enter key to load new value
or enter key to skip
dA 226
Use up/dn keys to obtain 20mA ouput on o/p1 then enter key to load
new value or enter key to skip
dA 226
Use up/dn keys to obtain 20mA ouput on o/p2 then enter key to load
new value or enter key to skip
Press save key to save and exit or Shift plus save keys to abort
Error and Alarm messages
ct Hl
CT current is more than 50% above set range
Alternates Pt 100 & FAUlt PT100 fault, i.e. Open or short circuit on PT100 circuitry
5Et Err
Press ‘up’ key to return to defaults
Cal Err
Press ‘up’ key to return to defaults
PK Err
Press ‘up’ key to return to defaults
IPFAIL
Isolated input section failure
2.9.1 Entering Modbus parameters
Hold down Shift and press Enter (Ã) for approx 2 seconds (display reads ‘5EtuP’) until display reads ‘rEAD4‘
before releasing the enter key, display shows “6rl9Ht”. Press the enter key again
-----0
Display with
key pressed
nEt-7Net
BAud
colL6
Enter password 77 to access Modbus parameters
Display with
Remarks
Key released
Adr 2
Serial address number, valid range 0-99
A5c/rtU
Toggle between ASCI or rtu using the up key
4.8/9.6/57.6
Baud rates, 4800, 9600 or 57,600, use up key to toggle
d4 30
Time period before 852 returns to local control, valid range 1-90 mins
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Press save key to save and exit or Shift plus save keys to abort
2.10.1
Modbus Holding register
(Note: Modscan32 has been used for illustration, demo & full versions can be obtained from www.win-tech.com)
The password is 00273 (see Modscan screen print below) The password remains operative for approximately 5
minutes during which time the Trip relay is inhibited. To exit before time-out enter invalid password.
Therefore the holding register has a ‘length’ of 28 for ASCII
mode and 40 for RTU mode. The password is entered into
register 1, this allows 5 minutes before timing out, to exit
before timeout simply enter invalid password. (Note: Do not
attempt to move to another section without correctly exiting
or waiting for the time-out period).
40001: Password
40002: Alarm ON value
40003: Alarm OFF value
40004: Alarm debounce time
40005: Pump ON value
40006: Pump OFF value
40007: Pump debounce time
40008: Fan ON value
40009: Fan OFF value
40010: Fan debounce time
40011: Trip ON value
40012: Trip OFF value
40013: Trip debounce time
40014: Hotspot temperature
40015: Top Oil temperature
40016: Peak temperature
40017: CT current in mA
40018: CT current as percentage
40019: Returns register 19
40020: Returns register 20
40021: Returns register 21
40022: Hotspot temperature
40023: Top Oil temperature
40024: CT current in mA
40025: Returns register 25
40026: Peak temperature
40027: Returns register 25
40028: Returns register 25 Last valid register for ASCII mode
Note: 40 registers are valid for RTU mode
Temperatures shown here are X10, i.e. 750 shown = 75.0°C.
Entering an invalid password, invalid temperature or other
‘out of range’ value will result in Modbus exception.
2.10.2
Modbus (Coil status)
The relay activity can be recorded and modified using the coil status register,
Note: When operating the 852Plus under Modbus it must be recognised that certain commands issued to the
852Plus will require full consideration of the consequences, i.e. In the event that an Alarm relay is forced off then
this will not become active again until either the unit has been powered down and re-powered again or the time
period, set under password 77 in the 852 has expired
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2.10.3
Modbus (Input register)
Allows the time, date and peak temperature to be recorded (peak temp, mins, hrs, day, month, year, actual temp,
top oil temp plus Pump CT value, Fan CT value, SP value & CN value
2.10.4
Modbus (Input status)
Allows the status of the four digital inputs to be recorded (Only works when in Contact mode, otherwise zero’s)
2.10.5
Modbus connection example
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2.11
Returning the 852 to default settings
(This does not affect factory calibration of PT100, CT input & analogue output)
Hold down Shift and press Enter (Ã) for approx 2 seconds (display reads ‘5EtuP’) until display reads ‘rEAD4‘
before releasing the enter key, display shows “6rl9Ht”. Press the enter key again
-----0
Enter password 3381 and unit will return all settings, relays etc to default settings
(except factory calibration) display reads “dEFlt5” before returning to normal.
Please note: If at any time an error message appears when powering up press the up key to return the value to
the default value.
2.12
Relay Test Mode
This mode simulates a rising and falling temperature to allow the user to observe correct operation of the relays.
-----0
Enter password 1508 and unit will de-energise all relays and return the unit to 0°C the display
will then slowly ramp up at approximately 1°C per second (pressing and holding the up key will increase this to
4°C per second). This allows the user to observe the relays switching on at their set values (to temporarily halt
the rising temperature press and hold the enter key (Ã)) This will be necessary as the relay timers remain
operational. Note: When ‘PT100 Fault’ is enabled this inhibits the display from showing the rising/falling
temperature and Pump relay remains energised, Fan, Alarm & Trip relays are also inhibited.
When the temperature reaches 200°C the temperature will decrease at approximately 1°C per second (pressing
and holding the down key (shift key + up key) will increase the rate to 4°C per second). This allows the user to
observe the relays switching off at their set values (to temporarily halt the falling temperature press and hold the
enter key (Ã)).
Notes: a) When in ‘Relay test mode’ the Top Oil key remains operational. b) Analogue output 1 follows the
indicated temperature (Analogue output 2 continues showing Top Oil or CT as set by user). c) The only means
of aborting this routine is to remove the power.
2.13
Password list
000099 = Commissioning
(Flashing “c” on the left denotes commissioning mode, to abort: switch off unit!)
003381 = Enters unit to Defaults (except calibration, press save to keep or abort to abort)
000042 = Adjust relay parameters
000066 = Modify Settings parameters
XXXXXX = Calibration of PT100, CT input and analogue outputs (Factory settings only)
000077 = Modbus address, type, Baud rate and time-out times
000101 = Training of CT inputs for Fans and Pumps CT
001508= Relay Test mode (Note: In this mode the relays will not operate when the ‘PT100 Fault’ message shows)
000141 = Auto Cool mode
000033 = Allows the Fan and Pump relays to be ‘inverted’ or ‘normal’
Normal: This mode energises the relays at their setpoint and de-energises at the falling temperature
setpoint (Note: Ensure links H10 & H11 are correctly set for this mode, see 3.2.1 for details).
Inverted: This mode de-energises the relays at their setpoint and energises at the falling temperature
setpoint, this allows the contacts to be set for normally closed, which means the Fan and Pump will
automatically be running when the power is removed from the 852 (Note: Ensure links H10 & H11
are correctly set for this mode, see 3.2.1 for details).
3.0
Electrical Installation
When tightening the terminal blocks it is imperative that the terminals are not over-tightened as a
breakage may occur, this is especially important for the Power supply and CT inputs. Ashridge
Engineering Ltd assume no liability where terminal posts are broken.
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3.0.1 Mechanical Installation
Where the 852Plus units are installed in a south facing position the use of sunshades should be
considered to prevent excessive temperatures occurring and therefore reducing the component life
expectancy.
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3.1
Electrical wiring
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3.1.1 Wiring Diagram
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3.2
Terminal arrangement (Wall mounted version)
3.2.1 CT input conditioning & Relay O/P link arrangements (Wall mounted
version)
3.2.2 Selection of ‘Digital input’ type
ACCESS TO THE LINKS NOTED ABOVE NECESSITATES THE REMOVAL OF THE
COVER. IT IS IMPERATIVE THAT ALL SOURCES OF POWER ARE MADE SAFE
PRIOR TO THE REMOVAL OF THE COVER.
Before any changes are made it is recommended that the required changes are identifying and
noted before making changes. Static precautions must also be taken when making link
changes
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a)
With the link fitted as type ‘C’ a simple volt free contact is required between the common and
Pp (for Pump) input or Fn for the Fan input.
With the link fitted as type ‘A’ an external CT is required (10A/10mA, i.e. developing
approximately 2.2V @ 10mA across the internal 430R Burden resistor).
With the link fitted as type ‘B’ any external CT may be used that develops approximately 2.2
Volts across its own burden resistor.
Input SP is a closed contact only input. This is used to remotely switch on/off the Pumps and
Fans. I.e. when a closed contact is applied between the SP and the common terminals the Pump
and Fan will switch on, simultaneously after a short delay until the closed contact is removed.
Input CN is currently unassigned.
b)
c)
d)
e)
3.2.3 Selection of Relay output types
a)
b)
Use the table above to select the appropriate relay output type, bearing in mind that the
‘watchdog’ relay will be energised while the PT100 input, self check and power supplies are
healthy.
All other relays energise at their respective operating points.
3.2.4 Terminal arrangement (Panel mounted version)
3.2.5 Selection of ‘Digital input’ type (See 3.2.1 for link assignment details)
a) With the link fitted as type ‘C’ a simple volt free contact is required between the common and Pp (for
Pump) input or Fn for the Fan input.
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b) With the link fitted as type ‘A’ an external CT is required (10A/10mA, i.e. developing approximately
2.2V @ 10mA across the internal 430R Burden resistor).
c) With the link fitted as type ‘B’ any external CT may be used that develops approximately 2.2 Volts
across its own burden resistor.
d) Input SP is a closed contact only input. This is used to remotely switch on/off the Pumps and Fans. I.e.
when a closed contact is applied between the SP and the common terminals the Pump and Fan will
switch on, simultaneously after a short delay until the closed contact is removed.
e) Input CN is currently unassigned.
3.2.6 Selection of Relay output types
f)
Use the table above to select the appropriate relay output type, bearing in mind that the ‘watchdog’
relay will be energised while the PT100 input, self check and power supplies are healthy.
g) All other relays energise at their respective operating points.
3.3.1 Dimensions (DIN 144 version)
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3.3.2 Dimensions (Wall mounted version)
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4.
Typical displays from 852Plus
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5.
852Plus Application note 1
Using external CT's to monitor the Fans and Pump running currents & control Cool Fail function.
The winding or Hot Spot differential temperature is calculated by the 852Plus using a combination of the CT
input, the Fan (Fn) & Pump (Pp) Digital inputs and the remote Fan & Pump operation digital input (SP). It is
therefore imperative that the following methods to achieve this are fully understood before commissioning.
1
Under settings password (66) ensure that 'type' is set to 'CT' i.e.:
oP
t4PE
2 4-20/0-10/0-20
ct/contact
dEU
10
Select the output type using the up key
Toggle between cool fail input types as required using up key (ñ)
Plus or minus % of input deviation for ct type cool fail inputs
2
Ensure that the PCB links (H5 & H6, see page 10 & 12 of manual) are set accordingly. Initially
select Burden resistor Rx and CT turns ratio to provide approximately 1.5V RMS at the normal
running current (This provides a reading of approximately 70 on the 852Plus Fan or Pump digital
input).
3
Ensure that wiring is complete, working correctly and that all site safety procedures have been
followed before continuing.
4
Teach mode
Hold down Shift and press Enter (Ã) for approx 2 seconds (display reads setup ) until display reads ready
before releasing the enter key, display shows bright Press the enter key again -----0. Enter password 101
to access Teach mode parameters
After entering the password the unit displays the Fan and Pump running currents (The Pump on the left and the
Fan on the right) i.e.
47
48
The CT turns ratio and burden resistor values should be calculated to provide readings in the
range of 45 to 75 (1.5V RMS into the 852plus digital input terminals indicates a running current of 70). In
practise the readings under normal running conditions may vary considerably from the calculated
values and where this is the case the turns ration/burden resistor should be re-selected to bring the
readings within 40 to 85 maximum.
When satisfied with the readings press the save key
Dev f
Dev p
Min 2
Select the Fan deviation (expressed as a percentage of reading saved) that will cause the
Cool Fail relay to energise. Press Save to save and continue or enter to continue without saving.
Select the Pump deviation (expressed as a percentage of reading saved) that will cause the
Cool Fail relay to energise. Press Save to save and continue or enter to continue without saving.
Select the number of minutes before the Cool Fail relay energises after the start of the deviation
Press Save to save and continue or enter to continue without saving.
Note 1: When used in CT digital input mode the 2 off CT running currents may be monitored at any time by
pressing and holding down the 'Shift' and 'CT' keys.
Note 2: When used in this mode and the Pump fails to operate with the fans operating normally, the CoolFail message and relay will operate, however the 'Hot Spot' gradient will remain in the ONAN state. Where
the Fan fails to work but the Pump operates normally, the Cool-Fail message and the relay will operate and
the 'Hot Spot' gradient will continue to operate correctly.
Note 3: Where the forced cooling consists of only fans or pumps (but not both!) connect the two digital
inputs (Fn & Pp) together using a wire link.
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852Plus wiring arrangement for CT type digital input where Transformer is fitted with Fan and Pump
When commissioning and verifying the 'load' CT input it is important to ensure that the correct digital inputs are made
as these determine the appropriate cooling gradient. For instance if a full 5A (OFAF) input is applied and the digital
inputs are left in the Natural cooling state the 852Plus will remain on the ONAN gradient resulting in a much higher
temperature than expected.
852Plus wiring arrangement for CT type digital
852Plus wiring arrangement for CT type digital
input where Transformer is fitted with Pump only
input where Transformer is fitted with Fan only
(Ensure that Pump and Fan ON & OFF settings are identical) (Ensure that Pump and Fan ON & OFF settings are identical)
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Guidance notes regarding Wedding Ring CT, Burden Resistors and Voltage Inputs
1.
The 852Plus monitors fan and pump running currents by feeding voltage signals into the fan and
pump digital inputs (Although described as "digital inputs" these do, in fact accept three types of
input, i.e. (i) simple 0 or 1 digital input with links set as type C, (ii) dc analogue input when set as
type A or B, (iii) ac analogue input when set as type A or B). The voltages, nominally 1.5V RMS to
provide a reading of 70, are derived from externally mounted wedding ring CTs and burden resistors.
2.
Number of wedding ring CT primary turns and burden resistor values are derived from the table.
3.
The values listed below assume the use of a 10/0.01 (0.01VA) CT (OD=25, ID=12mm) and are
given as guidance only.
4.
Before completion the correct links MUST be identified and selected on the 852 PCB otherwise the
unit will not have the correct current ranges. (H5 & H6, see page 10 & 12 of manual)
5.
During commissioning it may become apparent that the turns ration/burden resistor values may be
incorrect and that some ‘site tuning’ may be required.
Note: Approximate RMS voltage input to 852Plus digital input terminals:
1.0V RMS = running current reading of 47
1.5V RMS = running current reading of 70
Pump or Total Fan Current
Range (A)
1.00 – 2.00
2.00 – 4.00
3.00 – 5.00
5.00 – 8.00
7.00 – 10.00
10.00-16.00
12.00-21.00
Reading
35 - 70
37 – 75
41 – 69
46 – 74
48 – 70
47-74
46-80
No of Primary
Turns
5
4
3
2
1
1
1
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Burden Resistor Ω
150
100
100
100
150
100
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6.
852Plus Application note 2
Using contact closure from Fans and Pump contactor closure to control Cool Fail function.
The winding or Hot Spot differential temperature is calculated by the 852Plus using a combination of the CT
input, the Fan (Fn) & Pump (Pp) Digital (inputs and the remote Fan & Pump operation digital input (SP). It
is therefore imperative that the following methods to achieve this are fully understood before commissioning.
Under settings password 66 ensure that 'type' is set to 'Contact closure' as shown below and that the PCB
links are set accordingly.
oP
t4PE
dEU
2 4-20/0-10/0-20
ct/contact
10
Select the output type using the up key
Toggle between cool fail input types as required using up key (ñ)
Plus or minus % of input deviation for ct type cool fail inputs
Where Fans and Pumps are used.
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Where Pump only are used.
Where Fans only are used.
Note 1: When used in this mode and the Pump fails to operate with the fans operating normally, the CoolFail message and relay will operate, however the 'Hot Spot' gradient will remain in the ONAN state. Where
the Fan fails to work but the Pump operates normally, the Cool-Fail message and the relay will operate and
the 'Hot Spot' gradient will continue to operate correctly.
Note 2: Where the forced cooling consists of only fans or pumps (but not both!) connect the two digital
inputs (Fn & Pp) together using a wire link.
Note 3: Main CT Calibration check: It is important to note that it is not possible to check the calibration of
the main CT until the Cool Fail system has been calibrated as the 852Plus will not switch from the ONAN to
the OFAF gradient until the Pump is 'seen' to be working correctly.
For example: Where a CT input of 5 Amps has been input and the 852Plus has not initiated the Fans and
Pumps the 'Hot Spot' reading will remain on the ONAN gradient and the 'Hot Spot' reading will appear too.
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7.
Application note 3:
Step Change mode:
Used where a high initial CT current could cause the core to overheat before the temperature rises
sufficiently to switch on the Pump at the normal pre-set temperature. (See manual pages 2 & 5)
Under settings password (66) ensure that '0n-5t' is set to '5t' i.e.:
t-LA9
nin 0
0-10 (1 min steps)Exponential timer, simulates thermal lag in transformer coil)
0n-5t
onAn/5tEP
tHrE5H
A 2.500
tlnE
nln 90
Time before the Pump returns to local control (range 1-240 minutes)
roLLAU
AU
Rolling average filter to reduce display flicker (range 0-10 secs, default 2)
2
Toggles using up key (ñ) if 5tEP is chosen the next parameter is
This sets the CT current threshold for the step change (after the CT current
has been higher than the threshold for more than 90 seconds)
The first parameter is the CT current required to initiate this function (The CT input must remain above this
point for 90 seconds before the function becomes active).
The second parameter sets the time period, in minutes for the pump to remain energised after the CT current
has returned to normal.
Step Change mode uses the 'LOAD' or CT input to override the normal method of starting the Cooling
system and start the circulating pump for a predetermined period.
In this mode the CT current must remain above a threshold value (as set by the user) for 90 seconds before
the function becomes active. Once initiated the Pump will remain energised for the time period (set by the
user) before returning to normal 'Hot Spot' temperature controlled operation.
For instance: After this time period expires and the transformer temperature is below the Pump 'Off' value
and the CT current is below the threshold value the pump relay will de-energise.
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8.
Commissioning
Checking the cooling gradients and CT inputs
1
Correctly set the ONAN and OFAF conditions under password 66 and save.
2
Ensure steady Top Oil temperature, either using PT100 simulator or by hot bath technique with
temperature below Fan and Pump switch ON point.
3
Simulate a CT input for ONAN (Naturally Cooled) load, this should be confirmed by pressing
the CT (Amps) key. The Hot-Spot temperature will now indicate the Top oil temperature plus
the offset used for the ONAN setting.
a. Note: Where the T-Lag has been used this will add an exponential timer and the Hot-Spot
temperature will take up to 25 minutes to stabilise.
1
Ensure steady Top Oil temperature, either using PT100 simulator or by hot bath technique with
temperature above Fan and Pump switch ON point or manually switch on fans and pumps. At
this point it is important to ensure that Digital inputs are working correctly (see application notes
1 & 2).
2
Simulate a CT input for full load, this should be confirmed by pressing the CT (Amps) key. The
Hot-Spot temperature will now indicate the Top oil temperature plus the offset used for the
OFAF full load setting.
a. Note 1: Where the T-Lag has been used this will add an exponential timer and the Hot-Spot
temperature will take up to 25 minutes to stabilise.
b. Note 2: The 852Plus will remain on the ONAN gradient until the digital inputs are operating
correctly (see application notes 1 & 2).
Checking the relay operation
Enter password 1508
Enter password 1508 and unit will de-energise all relays and return the display to 0°C the display will then slowly ramp
up at approximately 1°C per second (pressing and holding the up key will increase this to 4°C per second). This allows
the user to observe the relays switching on at their set values (to temporarily halt the rising temperature press and hold
the enter key (Ã)) This will be necessary as the relay timers remain operational. Note: When ‘PT100 Fault’ is enabled
this inhibits the display from showing the rising/falling temperature and Pump relay remains energised, Fan, Alarm &
Trip relays are also inhibited.
When the temperature reaches 200°C the temperature will decrement at approximately 1°C per second (pressing and
holding the down key (shift key + up key) will increase the rate to 4°C per second). This allows the user to observe the
relays switching off at their set values (to temporarily halt the falling temperature press and hold the enter key (Ã)).
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9.
Series 852Plus Record Sheet
User setting
NA
Details:
Serial No:
Firmware Version:
User password (42)
Alarm ON (Default 90.0°C rising)
Alarm OFF (Default 85.0°C falling)
Alarm relay de-bounce time (Default 3 seconds, max 60 secs)
Pump ON (Default 75.0°C rising)
Pump OFF (Default 55.0°C falling)
Pump relay de-bounce time (Default 3 seconds, max 60 secs)
Fan ON (Default 75.0°C rising)
Fan OFF (Default 55.0°C falling)
Fan relay de-bounce time (Default 3 seconds, max 60 secs)
Trip ON (Default 120.0°C rising)
Trip OFF (Default 115.0°C falling)
Trip relay de-bounce time (Default 6 seconds, max 60 secs)
NA
User password (66)
Grad User enters number of gradients required (1, 2 or 3)
(3 grad shown)
ONAN (Thermal image offset in °C, range 0-200, Default 15°C)
CT amps (For the ONAN offset in amps, Default 2.500 Amps)
ONAN 'H' (Default 1.0)
ONAN 'y' (Default 1.6)
ONAF (Thermal image offset in °C, range 0-200°C, Default 16°C)
CT amps (For the ONAF offset in amps, Default 3.75 Amps)
ONAF 'H' (Default 1.0)
ONAF 'y' (Default 1.6)
OFAF (Thermal image offset in °C, range 0-200°C, Default 17°C)
CT amps (For the OFAF offset in amps, Default 5.00 Amps)
OFAF 'H' (Default 1.0)
OFAF 'y' (Default 1.6)
Transfer time (ONAN to OFAF and visa verca, Default 480 seconds)
Thermal lag time (Default 0 minutes)
Toggles ONAN or step (Default ONAN)
(If step then next step=thresh, Default 2.500 Amps)
Time for Pump to remain active (Default 90 minutes)
Rolling Average (default 2)
O/p 1 (Use up key to toggle between 4-20, 0-10, 0-20mA, Default 4-20mA)
Range (0-200, 0-150, 30-150 degrees C, Default = 0-200)
O/p 2 (Use up key to toggle between t/oil or ct (Default t/oil)
O/p 2 (Use up key to toggle between 4-20, 0-10, 0-20mA, Default 4-20mA)
Toggles Contact, ct or none (Default contact)
Deviation (when in ct mode, Default 10)
Delay before cool fail message (Default 2 minutes)
Relay contact link settings (Contact mode shown in de-energised condition)
Note the Watchdog relay de-energises in fault condition, i.e. the relay remains energised when normal.
Watchdog
Alarm
Trip
Pump
Fan
Cool Fail
N/O
N/C
N/O
N/C
N/O
N/C
N/O
N/C
N/O
N/C
N/O
N/C
Calibration and Inspection details (Tick boxes and make notes as appropriate)
PT100 calibration
Bump test
CT calibration
Conformal coating
O/P calibration
100 hour (minimum) soak test
Embedded Serial number
Labels attached & settings checked
Relays tested
Check Cool Fail timer (2 mins)
24Vdc and analogue outputs
Final inspection
Time & Date set
Signature & date
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10.
Notes :
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