Download R4076E LFAA

Midos
Types LFAA 101, 102
Auto-Reclose Relay
Figure 1: LFAA relay with hinged front cover open to show the modular construction
Features
Models Available
Benefits
● Selectable single and/or three
phase auto-reclosing
LFAA 101
● Wide choice of scheme logic
options
● Suitable for feeders controlled by
one or two circuit breakers
● Number of reclosures can be
selected
● Dead times, close pulse and
reclaim time are independently
adjustable
● Scheme logic options can be
selected
● User friendly inbuilt keypad and
menu system
● Built-in test facilities
● Automatic scheme
documentation via ladder
diagram
2
for application to feeders switched by
a single circuit breaker
LFAA 102
● Suitable for all transmission feeder
protection schemes
for application to feeders switched by
two circuit breakers
● Simplified commissioning via inbuilt
test feature
● Greater setting flexibility
● Comprehensive analysis of auto
reclose attempts
Signals
from
external
plant
DC auxiliary +
supply
VX1
–
Opto-isolators
Auxiliary
relay outputs
Micro-processor
+6.5V
+19.5V
–19.5V
+24V
0V.
H13
DC/DC converter
H14
LED
indications
Serial &
parallel
I/O ports
LCD
Keypad
Signals
to external
plant
Operator interface
Figure 2: LFAA relay block diagram
phase auto-reclose if protection
re-operates during the reclaim time
after the first reclose
Application
The LFAA auto-reclose relay provides
facilities for single or two-shot
reclosures of one or two circuit
breakers following their tripping for a
fault on an overhead line. The
reclosures can be selected to be either
high speed single-phase, or high
speed or delayed three-phase.
When three-phase reclosure is desired
the equipment will convert any single
or two-phase tripping into three-phase
tripping before initiating the reclosure.
For schemes with two circuit breakers
the reclosure of the second circuit
breaker can be either simultaneous
with the first circuit breaker or it can
be sequential. In the latter case the
reclosure of the second circuit breaker
must naturally be a delayed three
phase reclosure.
Different operating cycles can be
selected using the keypad on the relay
front-plate. These allow the relay to
perform various combinations of the
following cycles:
One breaker schemes (LFAA 101)
●
●
Single shot scheme:
- single phase auto-reclose
- single phase or three phase - auto
reclose, depending on type of
fault
- three phase auto-reclose for all
types of fault
Two shot scheme:
any of the above cycles for the first
shot, followed by delayed three-
Two breaker schemes (LFAA 102)
●
Combinations of single and three
phase auto-reclose as above
●
Circuit breakers can be closed
simultaneously or sequentially on
the first shot
A block diagram is shown in Figure 2.
Description - Scheme
Scheme initiation enabling conditions
An auto-reclose cycle is initiated by
protection operation. Auto-reclose of a
specific circuit breaker is enabled
provided that, immediately prior to the
protection operation:
- the circuit breaker is closed
- The ‘Energy’ input from that circuit
breaker indicates sufficient stored
energy to perform an auto-reclose
cycle
- auto-reclose for that circuit breaker is
not switched out of service and is not
locked out
Scheme initiation
Single phase auto-reclose
LFAA 101 and LFAA 102
For single phase auto-relose, a phaseto-earth fault on any one phase will
initiate single phase tripping and autoreclose of the faulty phase only. A
fault involving two of more phases will
result in three phase tripping. For this
purpose the scheme will convert any
two pole trip of the circuit breaker into
a three pole trip.
LFAA 102
Single phase auto-reclosures can be
either of the simultaneous or
sequential type depending on the
programme selected. Whenever
simultaneous reclosure is selected,
both circuit breakers will trip single
phase and reclose simultaneously
after the single phase dead time.
Whenever sequential reclosure is
selected, the leader circuit breaker
will trip single phase and reclose after
the single phase dead time but the
follower circuit breaker will grip three
phase and reclose after the selected
follower circuit breaker delay time has
elapsed.
Three phase auto-reclose
Three phase auto-reclose can be
initiated by single phase faults only,
multi-phase faults only or any fault
depending on the scheme selected
and whether the auto-reclosure is first
or second shot. In the case of faults
which result in the tripping of one or
two poles of the circuit breaker, the
relay will convert the single or two
pole trip into a three pole trip before
initiating three phase reclosing.
LFAA102: auto-reclose of follower
circuit breaker
The follower circuit breaker can be
automatically switched to the autoreclose programme originally selected
for the leader circuit breaker if any
one of the initiation enabling
3
conditions for the leader circuit
breaker is not satisfied. In the
sequential single phase or single and
three phase auto-reclose programme,
one or two shot, the follower circuit
breaker will be automatically switched
to perform a single phase trip on
scheme initiation if any one of the
above conditions exists. Single phase
reclosure of the follower circuit
breaker will occur at the end of the
single phase dead time.
+ DC auxilliary supply Vx2Switch in
–
B1
1
Switch out
B3
2
'A' PH
'A/R initiate'
signals
from
protection
'B' PH
'C' PH
3 PH
B5
3
B7
4
B9
5
B11
6
Intertrip receive
B13
'Block A/R' from protn.
B15
Line voltage monitor
B17
Timer test start
B19
Developing faults
(3)
"Stop"
B21
For single phase only auto-reclose
programmes, the development of a
fault on to a previously unaffected
phase, if detected during the single
pole dead time and before the circuit
breaker reclosure, will result in a three
phase trip and scheme lockout.
(4)
"Enable"
B23
If any of the above conditions exist
prior to initiation of a three phase
auto-reclose, the follower circuit
breaker will trip three phase followed
by reclosure at the end of the three
phase dead time.
For single and three phase autoreclose programmes, the development
of a fault on to a previously
unaffected phase, if detected during
the discrimination time and before the
circuit breaker reclosure, will result in
a three phase trip and conversion of
reclosing from single phase to three
phase. If the developing fault occurs
after the discriminating time has
elapsed the relay will trip in all three
phases and lock out.
Scheme reset
Single breaker schemes (LFAA 101)
The scheme will automatically reset if
the reclaim time expires and the
circuit breaker is closed.
7
8
9
10
11
12
B25
B27
(1)
CB1 aux. switch
B2
(2)
CB1 healthy
B4
Microprocessor
17
CB1 dead line charge/
sync. check
CB1 separate
sync. check
18
B6
19
B8
20
Reset CB1 lockout
Reset CB1 maint.
counter
B10
(1)
CB2 aux. switch
B14
(2)
CB2 healthy
B16
21
B12
22
23
CB2 dead line charge/
sync. check
CB2 separate
sync. check
24
B18
25
B20
26
Reset CB2 lockout
B22
Reset CB2
maint. counter
B24
CB2 stop
Two breaker schemes (LFAA 102)
The auto-reclose of the breakers will
automatically reset at the end of the
reclaim time if both breakers are
closed. If the auto-reclose of only one
circuit breaker is in progress at the
end of the reclaim time, the scheme
will reset if this particular circuit
breaker is in the closed position but
lock out if it is in the open position.
13
Notes:
1. Each 'CB AUX SWITCH' should comprise
either three normally open (52a) auxiliary
switch contacts (one per pole), connected in
series or three normally closed (52b) auxiliary
switch contacts (one per pole), connected in
parallel.
2. Each 'CB HEALTHY' contact is a contact on the
circuit breaker which operates when the CB is
ready to perform an auto-reclose cycle
(for example, closing spring fully charged or
gas pressure high). The contact can be either
normally open or normally closed.
27
28
B26
B28
29
3. If two relays are main and backup autoreclose on the same feeder, terminal B21 on
each relay can be energised by an 'Autoreclose in Progress' signal from the other
relay, to provide mutual interlocking.
4. If auto-reclose is permitted only under
specified conditions, eg parallel circuit in
operation, B23 can be controlled by a contact
which operates when the specified
conditions are satisfied.
Figure 3: LFAA 101 and 102: External connections to opto-isolator inputs
4
PS-1
H3
H4
PS-2
H5
H6
Note:
Power supply failure
alarm (see note)
Module 1
Module 2
G3
G5
RL1
Under healthy operating conditions the
power supply fail relay is held on.
The following conditions will cause the
relay to drop off:
– loss of dc supply
– loss of any internal dc rail voltage
G1
G4
G6
RL2
G2
RL3
G11
G9
RL4-1
G15
G13
RL4-2
G19
G17
RL5-1
G12
G10
RL5-2
G16
G14
CB1 A/R lockout
indication
RL17
RL7
RL8
RL12
RL13
RL14
G20
G18
G24
G22
G28
G26
G8
G7
G23
G21
G27
G25
F1
F9
F11
CB1 'phases not
together' protn.
inhibit
RL19
RL18
Trip CB1
3 phase
F2
F10
F12
Close CB1
F8
F16
F18
'CB1 close'
indication
RL22
F14
F22
F24
Bridge
CB1
trip circuits
RL23
F20
RL24
F28
F26
Initiate sync.
voltage
selection CB1
F15
F17
RL28
F13
RL29
F27
F25
Not used
CB1 maintenance
alarm
F21
F23
CB1 maintenance
lockout
RL30
E3
E5
'Auto-reclose
in Progress'
indication
F7
F4
F6
RL21
RL6
Module 3 (LFAA 102 only)
F3
F5
F19
Directional earth
fault protection
inhibit
inhibit power
swing blocking
RL33
E1
E4
E6
Not used
'Auto-reclose
in service'
indication
CB2 'phases not
together' protn.
inhibit
RL34
E2
RL35
E11
E9
RL36-1
E15
E13
RL36-2
E19
E17
RL37-1
E12
E10
RL37-2
E16
E14
RL38
E20
E18
RL39
E24
E22
RL40
E28
E26
RL44
E8
E7
RL45
E23
E21
CB2 maintenance
alarm
RL46
E27
E25
CB2 maintenance
lockout
Inhibit
zone 1 extension
Not used
CB2 A/R lockout
indication
Timer test
Not used
Trip CB2
3 phase
Close CB2
'CB2 close'
indication
Bridge
CB2
trip circuits
Initiate sync.
voltage
selection CB2.
CB2 control
See input 29 description
Figure 4: LFAA 101 and 102: External output contacts wiring
Scheme lockout
●
at the end of the three phase dead
time the correct voltage monitor or
check synchronism conditions are
not satisfied within the pre-closing
check time
●
if the closing pulse ends without
interruption and the circuit breaker
is in the open position
●
auto-reclose blocking is initiated
●
for certain conditions after an
interruption of dc supply
Single breaker schemes (LFAA 101)
Scheme lockout will block scheme
initiation and operation, preventing
automatic reclosure. It occurs for any
of the following conditions:
●
●
the circuit breaker is in the open
position at the end of the reclaim
time
the protection operates during the
reclaim time following the final shot
●
if the protection relay has not reset
or the circuit breaker has not
tripped within the trip fail time
5
Two breaker schemes (LFAA 102)
Circuit breaker lockout will block
scheme initiation and operation of the
relevant breaker, preventing
automatic reclosure; it occurs for any
of the following conditions:
●
●
●
●
●
6
ALARMS 1
AUTO RECLOSE
OUT OF SERVICE
if the auto-reclose of both breakers is
successfully initiated, the autoreclose of the affected CB will lock
out at the end of the reclaim time if
either one or both breakers are in
the open position
if the auto-reclose of only one circuit
breaker is in progress at the end of
the reclaim time, the scheme will
reset if this particular circuit breaker
is in the closed position but lock out
if it is in the open position
if the relay is initiated during the
reclaim time of a single shot
programme or during the reclaim
time following the final shot of a
two shot programme, the relay will
initiate three phase tripping and
lock out
both breakers will be locked out if
the correct voltage
monitor/synchronism check
conditions have not occurred within
the pre-closing check time. If the
leader circuit breaker has
successfully reclosed and the correct
conditions have not occurred within
the pre-closing check time after the
expiry of the follower circuit breaker
time, the follower circuit breaker
will be locked out.
the auto-reclose of the relevant
circuit breaker will be locked out if
that particular circuit breaker is in
the open position when the closing
pulse expires without interruption. If
the auto-reclose of the leader circuit
breaker locks out in this way, the
follower circuit breaker will inherit
the pre-closing check conditions
originally selected for the leader
circuit breaker.
After the follower circuit breaker
delay time, if the pre-closing check
conditions are satisfied, the follower
circuit breaker reclose pulse will be
initiated. For subsequent scheme
initiation with the leader circuit
breaker in the lockout state, the
follower circuit breaker will adopt
the auto-reclose programme
originally selected for the leader
circuit breaker
ALARMS 2
RELAY HEALTHY
SET
PARALLEL
SELECT/RESET
ACCEPT/READ
SERIAL
Figure 5: Operator interface
●
both breakers will be locked out if
auto-reclose blocking is initiated
●
both breakers will be locked out if
the protection relay has not reset or
the circuit breakers have not tripped
within the set ‘Trip Fail’ time after
scheme initiation.
The lock out condition is one of the
conditions indicated by the ALARMS 1
indication on the front of the relay.
Block auto-reclose
This is an input which initiates
blocking, causing three phase tripping
and lock out.
Manual closing of the circuit breaker
– status alarms 1, indicated by the red
led being stably lit
This group includes the lock-out
alarms
– compound alarms, indicated by the
red led flashing
This group includes the
maintenance lock-out alarm
– status alarms 2, indicated by the
amber led being stably lit
This group includes the auto-reclose
in progress alarm
– change alarms, indicated by the
amber led flashing
This group includes the
maintenance (pre-lockout warning)
alarm
If the circuit breaker is closed
manually on to a fault, the autoreclose must be inhibited. An
‘initiation inhibit’ condition is
activated when either of the circuit
breakers moves from open to closed
when there is no auto-reclose cycle in
progress (ie, closed by manual
control). The inhibit is removed when
the circuit breaker has remained
closed for the set manual close time.
The alarms are enabled when the
appropriate condition occurs in the
ladder logic, and can then be read
without removing the relay front
cover, by a combination of keystrokes
on the ACCEPT/READ and
SELECT/RESET keys on the relay front
panel.
Switching auto-reclose relay
in/out of service
The fourth led (green) is the relay
healthy indication.
The LFAA relay can be switched in or
out of service from a remote point.
When out of service, the relay OUT
OF SERVICE amber indicator lights on
the front of the relay.
Indications and alarms
The relay has four light emitting
diodes (led’s) on the front panel for
indications and alarms. The top two
(red and amber) are for alarms, which
are in four groups:
The third led (amber) is the out of
service indication.
Test facilities
The LFAA relay provides the customer
with the facility to test the following
parameters:
– to read the state (ie, on or off) of
each input to, and output of, the
relay
– to monitor the operation of all timers
via a dedicated input and output
– with the front cover removed and
the relay out of service, the state of
each relay can be changed
Relay inputs
Input connections are shown in
Figure 3.
Input functions are as follows:
1. TERMINAL B1:
When this input is energised, either
momentarily or permanently, the autoreclose scheme is switched in to
service, provided input terminal B3 is
not also energised.
2. TERMINAL B3:
When this input is energised, either
momentarily or permanently, the autoreclose scheme is switched out of
service.
3. TERMINAL B5:
4. TERMINAL B7:
5. TERMINAL B9:
6. TERMINAL B11:
These inputs are energised by single
phase or three phase trip repeat (A/R
initiation) contacts on the protective
relays. If the protection does not have
a separate ‘3PH trip’ output, input 6
to terminal B11 is not required.
7. TERMINAL B13:
This input may be energised by a
contact on an intertrip receive repeat
relay if a direct intertripping scheme is
in use. If this input is energised, the
auto-reclose relay will treat it as a
three phase fault.
8. TERMINAL B15:
This input is energised by the Block
A/R contact of the feeder main
protection (eg, output 96 on
Micromho, Quadramho or Optimho).
If B15 is energised at any time during
an auto-reclose cycle, the scheme
locks out.
9. TERMINAL B17:
This input can be energised by a
normally open or normally closed
contact on a line voltage monitor
relay, to provide a line voltage
interlock. Please refer to publication
R4085 or R4094 for full details.
10. TERMINAL B19:
This input is used to start a timer test.
Please refer to Service Manual R5920
or R5930 for full details.
11. TERMINAL B21:
This is used when two relays operate
in a main/backup arrangement. See
Figure 3, Note 3.
21. TERMINAL B10:
If this input is momentarily energised
when CB1 auto-reclosing is locked out
CB1 A/R will immediately reset,
provided the condition which caused
the lockout has been cleared.
22. TERMINAL B12:
If this input is momentarily energised,
the CB1 maintenance counter fault
trips registers are reset to zero.
12. TERMINAL B2:
INPUTS 23 TO 29 ARE USED ONLY
ON LFAA 102:
See Figure 3, Note 4.
23. TERMINAL B14:
17. TERMINAL B2:
This input is energised by a normally
open (52a) or normally closed (52b)
auxiliary switch contact on the circuit
breaker CB1. For circuit breakers with
three separate single pole
mechanisms, input 17 should be
energised either by three 52a
contacts (one from each pole)
connected in series, or by three 52b
contacts connected in parallel.
Software function FNCT 14 should be
set ON if 52a contacts are used, or
OFF if 52b contacts are used.
24. TERMINAL B16:
18. TERMINAL B4:
This input may be energised by a
normally open or normally closed
contact which indicates that the circuit
breaker CB1 has sufficient stored
energy (eg, oil or gas pressure, or
spring fully charged) to perform a
complete trip/auto-reclose cycle.
Software function FNCT 15 should be
set ON or OFF depending on the
operating mode of the energy contact.
If no such contact is available on the
circuit breaker, this input may be left
de-energised, and FNCT 15 set ON.
25. TERMINAL B18:
26. TERMINAL B20:
27. TERMINAL B22:
28. TERMINAL B24:
Similar to corresponding inputs 17 to
22 but for CB2.
29. TERMINAL B26:
When two adjacent circuits in the
same bay of a one and a half switch
S/S are each controlled by an
LFAA 102 relay, the ‘CB2 CONTROL’
output (E7 - E8) on each relay should
be connected to energise input 29
(B26) on the adjacent relay. This
ensures that in the event of concurrent
auto-reclose cycles on both circuits,
the middle CB (CB2) can reclose only
when the required conditions are
satisfied for both LFAA relays.
19. TERMINAL B6:
This input in energised by a normally
open output contact on a voltage
monitor (dead line charge, dead bus
charge or synchronism check) relay,
and must be live at the end of a three
phase dead time (optional for first
shot - see FNCT 11) before the CB
close output can be given for CB1.
20. TERMINAL B8:
This input may be energised by a
normally open output contact on a
separate synchronism check relay, if
fast synchronising is required for CB1
- see publication R4085 or R4094 for
full details.
7
Description - Hardware
User Interface
Description - Software
The relay is housed in a 4U (178mm)
high case suitable for either rack or
panel mounting. The relay uses plug-in
modules which are individually tested
and calibrated in the factory. If
necessary, modules can be
exchanged without any need to
recalibrate the relay.
The front panel operator interface,
shown in Figure 5, consists of a 2 row
16 character alphanumeric liquid
crystal display (lcd) together with a
seven push-button keypad. With the
relay cover in position only the
SELECT/RESET and ACCEPT/READ
keys are accessible. Using just these
two keys, it is possible to view system
details, view (and clear) alarms, view
counters, view settings, view the status
of all opto-inputs and output relays
and perform a timer test. A menu
approach has been adopted such that
the operator, using the lcd, can easily
and efficiently access a whole range
of useful information.
The relay software is divided into
three main groups: the system
software, the logic controller software,
and the scheme logic.
A power supply module converts
power from a dc supply to internal
voltage rails. A power failure
monitoring circuit with alarm output
contact is provided.
A status input module receives
external plant status and protection
equipment status signals via optoisolated inputs.
A 16 bit microprocessor is used for
sequence control and timing functions.
It interfaces with the opto-isolated
inputs and output relays via an
address/data bus. Input and output
connections are shown in Figures 3
and 4 respectively.
The microprocessor module also
contains non-volatile read/write
memory (EEPROM) for settings and
relay status information, read/write
memory (RAM) for temporary data,
and read-only memory (ROM) for the
system and application software. The
system software resides in one pair of
ROM devices, and the application
software in another, separate pair. By
appropriate programming of the
application ROM, either standard or
special auto-reclose requirements can
be satisfied.
Two output relay modules are
provided in a basic single breaker
application (LFAA 101), and three
output modules are provided in a
basic two breaker application
(LFAA 102).
The power supply module converts the
auxiliary dc voltage into the regulated
dc voltage rails required by the relay.
High efficiency and isolation from the
auxiliary supply are achieved by the
use of a switching dc/dc converter. A
power fail monitoring circuit with two
alarm output contacts is included.
8
Security related commands, such as
changing settings, resetting counters
and testing output relays are only
available when the cover is removed,
and can be blocked under certain
specific conditions. See the service
manual and scheme description for
details of the conditions under which
the commands are blocked. Five pushbuttons, arranged in a cruciform
pattern, become accessible when the
front cover is removed; four of these
act as cursor keys for selecting
commands or altering parameters in
an easy to follow menu approach.
The SET key at the centre is used to
confirm entry of new settings.
The test sockets can be used to send
information about the relay to either a
serial or a parallel printer. The user
selects whether to transmit the
information to the serial or parallel
port. In addition, test points within the
relay can be monitored on the parallel
socket.
Remote communications
All the options available on the menu
are also available from a local or
remote terminal via an RS232C serial
communication port. Sockets are
provided on the front of the relay for
temporary connection and on the rear
for permanent connection. The rear
socket can also interface with a modem
for communication over a suitable link,
for instance a telephone line.
The system software is independent of
the application and is common to all
multi-modular hardware applications.
It consists of various diagnostic,
debugging, input/output, and multitasking handling facilities. It provides
a common software environment
within which different application
programmes can be developed and
operated.
The logic controller operating system
interfaces between the system
software and the scheme logic of the
application programme. It processes
the status input information, updates
the relay outputs and controls the
operator interface.
The scheme logic is the application
programme, defining how a relay
performs; it is presented in the form of
a ladder diagram. The ladder is an
easy to follow application diagram
consisting of contacts, timers, counters
and output relays. This approach
means that the user does not need to
understand complex programming
languages in order to understand the
relay application. Each relay scheme
is fully documented including a copy
of the ladder diagram appropriate to
that scheme.
Further Information
Full details of the selectable autoreclose cycles and scheme options are
given in separate publications:
LFAA 101 Scheme Description R4085
LFAA 102 Scheme Description R4094
Technical Data
Auxiliary voltage rating
Auxiliary voltage Vx (1)(dc)
Nominal (V)
Operative range(V)
(Relay power supply)
24/27
30/34
48/54
110/125
220/250
19.0 - 32.0
24.0 - 40.0
37.5 - 65.0
87.5 - 150.0
175.0 - 300.0
Auxiliary voltage Vx(2)(dc)
Nominal (V)
Operative range (V)
(Opto-isolator supply)
24/27
30/34
48/54
110/125
220/250
19.0 - 32.0
24.0 - 40.0
37.5 - 65.0
87.5 - 150.0
175.0 - 300.0
Note:
Vx (2) May be different from Vx (1)
Burdens (maximum)
Vx(1) or
Aux supply (W) Add to auxiliary supply burden (W)
Vx(2)
(Volts)
(No output
relays on)
Each input
24
27
30
34
48
54
110
125
220
250
8
8
8
8
8.5
8.5
8.5
9
10.5
11.5
0.025
0.030
0.030
0.040
0.060
0.090
0.110
0.150
0.250
0.350
Each output
RLO-RL7
RL8-RL13
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
0.4
Timers
Timer name
Limits
of settings (s)
Accuracy: greater of
0.01–2.0
± 2% or –10 + 20ms
high speed three
phase reclosing
0.01–200
± 2% or –10 + 20ms
delayed second shot
three phase reclosing
1.0–300
± 2% or –10 + 20ms
0.01–2.0
± 2% or –10 + 20ms
Dead Time
high speed single
phase reclosing
Discrimination time
Pre-closing check
1.0–200
± 2% or –10 + 20ms
Trip fail timer (LFAA 101)
(LFAA 102)
0.01–200
1.0–200
± 2% or –10 + 20ms
± 2% or –10 + 20ms
Reclose pulse
0.01–2.0
± 2% or –10 + 20ms
Reclaim time
1.0–300
± 2% or –10 + 20ms
Manual close time
1.0–200
± 2% or –10 + 20ms
Intertrip time
1.0–300
± 2% or –10 + 20ms
LFAA 102 only
Follower circuit
breaker delay time
(2 breaker schemes)
0.01–300
± 2% or –10 + 20ms
9
Contacts
Make and carry for 0.2s
7500VA (30A or 300V ac or dc maxima)
Carry continuously
5A ac or dc
Break
AC 250VA
DC 50W resistive
25W inductive, L/R = 40ms
(Subject to maxima of 5A or 300V)
Durability
Loaded contact
Unloaded contact
10,000 operations, minimum
100,000 operations minimum
High voltage withstand
Dielectric withstand
IEC 255-5:1977
2kV rms for 1 minute between all case
terminals connected together and the case
earth terminal.
2kV rms for 1 minute between all
terminals of independent circuits, with
terminals on each circuit connected together.
1kV rms for 1 minute across normally
open contacts.
High voltage impulse
IEC 255-5:1977
Three positive and three negative impulses
of 5kV peak, 1.2/50µs, 0.5J between all
terminals and all terminals and case earth.
Electrical environment
High frequency disturbance
IEC 255-22-1:1988 Class III
2.5 kV peak between independent circuits
and independent circuits and case earth.
1.0 kV peak across terminals of the same
circuit (except metallic contacts).
Fast transient disturbance
IEC 255-22-4:1992 Class III
2kV, 5kHz applied directly to auxiliary
supply
2kV, 5kHz applied directly to all inputs
Electrostatic discharge
IEC 255-22-2:1989 Class III
IEC 801-2:1991 Level 3
DC supply interruption
IEC 255-11:1979
EMC compliance
89/336/EEC
EN 50081-2:1994
EN 50082-2:1995
8.0kV - discharge in air with cover in place.
6.0kV - point contact discharge with cover
removed.
The unit will withstand a 10ms interruption
in the auxiliary supply, under normal
operating conditions, without de-energising.
Compliance with the European
Commission Directive on EMC is claimed
via the Technical Construction File route.
Generic standards were used to establish
conformity.
Product safety
10
72/23/EEC
Compliance with European Commission
Low Voltage Directive
EN 61010-1:1993/A2:1995
EN 60950:1992/A3:1995
Compliance is demonstrated by
reference to generic safety standards.
Atmospheric environment
Temperature
IEC 255-6:1988
Storage and transit -25°C to +70°C
Operating -25°C to +55°C
IEC 68-2-1:1990
Cold
IEC 68-2-2:1974
Dry Heat
Humidity
IEC 68-2-3:1969
Enclosure protection
IEC 529:1989
56 days at 93% RH and 40°C
IP50 (dust protected)
Mechanical environment
Vibration
IEC 255-21-1:1988
Response Class 1
Seismic
IEC 255-21-3:1993
Class 1
438
Rack Mounting
483mm (19”) rack details
dimensions to IEC297
7 max
31,75
±0,4
Removable
cover
432
Hinged front
panel
12,7
±0,4
Push button
projection 10mm max
450 MIN
10
177
U scale
U=44,45
101,6
10
465
483
Front
37
252
465,1 ±1,6
7
Allow a minimum of 50 for
terminal block & wiring
Side
10,6
Fixing hole detail
438
Tolerance between
any two holes
within a distance
of 1mm±0,4
Panel Mounting
Panel cut out
detail
400
200
Removable
cover
432
Hinged front
panel
Push button
projection 10mm max
180,5 191
10
201
177
10
443
Front
37
252
Side
440
Fixing Holes
Ø 5,4
Allow a minimum of 50 for
terminal block & wiring
All dimensions in mm Terminal screws: M4 x 8 brass cheese head with lockwashers are provided Mounting screws are not provided
Figure 6: Case outlines
Cases
Type LFAA are housed in multi-module
MIDOS cases.
(See Figure 6).
Information Required with
Order
Type of relay
LFAA 101 or LFAA 102
Auxiliary supply voltages
Vx(1) and Vx(2)
Case mounting
Rack or panel
11