Download VRDC-Hz - Atkinson Electronics Inc

ADJUSTABLE FREQUENCY SENSITIVE RELAY WITH TIME DELAY
VRDC-Hz
FEATURES
v Powered by a wide DC power range, 10.5 to
35V, or by 24V AC
v Adjustable thresholds for cut-in and cut-out
points between 50 & 75Hz over 100 to 260V AC
v Optional lockout input with user furnished “NC”
momentary push button switch
v 12 Amp SPDT relay contact
v Automatic reversible action with the cut-in, cutout adjustments
v Adjustable 0 to 255 sec. time delay on cut-in
v Compact size eliminates mounting problems
APPLICATIONS
v Low & high voltage cutoff and generator control
v Frequency based generator starting
v Hydro-electric power shut down
DESCRIPTION & OPERATION
The VRDC-Hz is a Adjustable Voltage Relay for AC
frequency applications. The VRDC-Hz can be used in
applications where a varying frequency is used to switch an
adjustable relay such as in generator control or a frequency
Hydro Power Plant load disconnect. The “cut-in” frequency,
“cut-out” frequency, and the time delay value are adjusted
on multi-turn potentiometers by measuring the respective
test points and adjusting the potentiometers per the set-up
instructions and chart on the back side of last page.
The VRDC-Hz uses a half-wave rectifier filter circuit which
allows the VRDC-Hz to operate from either a 10.5 to 35VDC
power source or a 24VAC power supply. The VRDC-Hz’s
input is internally scaled so that a 50 to 75Hz AC signal
equals 0 to 5VDC as shown in the chart on the back side of
this page. A lockout input, when connected to the minus of
the power input, keeps the relay from being de-energized
after being turned on. If the input signal drops below the
“cut-out” point, the lockout can be reset by opening the
circuit by removing the lockout wire from power minus or
depressing a normally closed pushbutton switch in the
lockout circuit. An LED lights when the relay is pulled in.
PHYSICAL CONFIGURATION
SPECIFICATIONS
SIZE:
3.2"L x 1.2"W x 0.75"H inches
ENCLOSURE:
Epoxy potted in PVC plastic
MOUNTING:
Double stick tape or snap track
POWER:
10.5 to 35V DC or 24V AC
LOAD CAPACITY:
12 Amps @ 28V DC, SPDT
12 Amps @ 240V AC, SPDT
HASCO KLT1C12DC12
INPUT SIGNALS:
50 to 75 Hz.,
For 100 to 260 V AC
THRESHOLD:
Cut-in @ 50 to 75 Hz
Cut-out @ 50 to 75 Hz
0.30 Hz min differential
TIME DELAY:
0- 255 seconds delay on energize
ACTION:
Direct - Energizes on increase
Reverse - Energizes on decrease
CURRENT DRAW:
Continuous - less than 8mA
Relay energized - 40mA
INDICATION:
LED indicates Relay is energized
TEMPERATURE:
-20 to 508C
RELAY LIFE:
100 million mechanical operations
ORDERING INFORMATION
VRDC-Hz-A - Adjustable frequency cut-in/out points
50 to 75 Hz, 0 to 255 second time delay.
VRDC-Hz-B - Adjustable frequency cut-in/out points
15 to 65 Hz, 0 to 255 second time delay.
The test points shown are for field calibration of the
“cut-in”, “cut-out”, and time delay potentiometers.
Special frequency ranges available by request.
ATKINSON ELECTRONICS, INC.
Web site: www.atkinsonelectronics.com
REV 5/03
Distributed by:
ADJUSTABLE FREQUENCY SENSITIVE RELAY WITH TIME DELAY
VRDC-Hz
CONNECTION DIAGRAM - WITH LOCKOUT
The VRDC-Hz frequency input (brown wire) is connected to the device being monitored. The lockout input (blue wire) is
connected to a normally closed push button switch and to the power supply minus (black wire). Upon the input reaching the “cutin” point the relay energizes and remains energized, even after the “cut-out” point is reached, until the push button switch is
depressed opening the lockout circuit. Once opened the relay de-energizes.
CONNECTION DIAGRAM - WITHOUT LOCKOUT
The VRDC-Hz frequency input (brown wire) is connected to the device being monitored. The lockout input (blue wire) is not
connected. Upon the input reaching the “cut-in” point the relay energizes after any time delay if set and remains energized, until
the “cut-out” point is reached.
ATKINSON ELECTRONICS, INC.
Web site: www.atkinsonelectronics.com
REV 5/03
Distributed by:
ADJUSTABLE FREQUENCY SENSITIVE RELAY WITH TIME DELAY
VRDC-Hz
ADJUSTMENT FORMULAS
50 TO 75 Hz
TIME DELAY
-
Vadj = Hz-50 X 0.20
Vadj = Time Delay (sec) X 0.01961
Vadj
-
Adjustment voltage at cut-in and cut-out test
points.
Minimum
Resolution: 0-5V Adjust voltage / 255 steps = 0.02V DC
ADJUSTMENT PROCEDURES
Input
Frequency
Ranges
Input
Frequency
Ranges
Time Delay
Cut-in/out
& delay
Tp volts
Input
Frequency
Ranges
Input
Frequency
Ranges
Time Delay
Cut-in/out
& delay
Tp volts
VRDC-Hz-A
VRDC-Hz-B
0-255 Sec
0-5VDC
VRDC-Hz-A
VRDC-Hz-B
0-255 Sec
0-5VDC
50 Hz
15 Hz
0 sec
0.0v
63 Hz
41 Hz
132.6 sec
2.600v
51 Hz
17 Hz
10.2 sec
0.200v
64 Hz
43 Hz
142.8 sec
2.800v
52 Hz
19 Hz
20.4 sec
0.400v
65 Hz
45 Hz
153.0 sec
3.000v
53 Hz
21 Hz
30.6 sec
0.600v
66 Hz
47 Hz
163.2 sec
3.200v
54 Hz
23 Hz
40.8 sec
0.800v
67 Hz
49 Hz
173.4 sec
3.400v
55 Hz
25 Hz
51 sec
1.000v
68 Hz
51 Hz
183.6 sec
3.600v
56 Hz
27 Hz
61.2 sec
1.200v
69 Hz
53 Hz
193.8 sec
3.800v
57 Hz
29 Hz
71.4 sec
1.400v
70 Hz
55 Hz
204.0 sec
4.000v
58 Hz
31 Hz
81.6 sec
1.600v
71 Hz
57 Hz
214.2 sec
4.200v
59 Hz
33 Hz
91.8 sec
1.800v
72 Hz
59 Hz
224.4 sec
4.400v
60 Hz
35 Hz
102.0 sec
2.000v
73 Hz
61 Hz
234.6 sec
4.600v
61 Hz
37 Hz
112.2 sec
2.200v
74 Hz
63 Hz
244.8 sec
4.800v
62 Hz
39 Hz
122.4 sec
2.400v
75 Hz
65 Hz
255.0 sec
5.000v
1. The “cut-in”, “cut-out” and “time-delay” pot adjustments are measured on the respective test points by a DC
voltmeter. The cut-in/out 0 to 5V DC represents 50 to 75 Hz AC input signal. The time delay 0 to 5V DC represents
0 to 255 sec delay on energize.
2. If the “cut-in” pot is greater than the “cut-out” pot then the relay energizes when the signal voltage is greater than
the “cut-in” point and de-energizes when the signal voltage drops below the “cut-out” point. If the “cut-in” point is less
than the “cut-out” point then the relay energizes when the signal voltage drops below the “cut-in” point and deenergizes when the signal voltage rises above the “cut-out” point. If the signal voltage differential between the “cutin” and “cut-out” adjustments is not at least 0.30 Hz in the 50 to 75 Hz range then the relay will not operate.
3. The time delay pot’s 0 to 5V DC represents 0 to 255 seconds. of time delay for the relay to energize on “cut-in”
for either reverse or direct mode. The input signal must exceed the “cut-in” point for the time delay value or the
timing action will start over. The “cut-out” action is instantaneous.
4. After adjusting the VRDC-Hz module, interrupt power (this re-sets the circuitry) to insure that the module operates
properly.
ATKINSON ELECTRONICS, INC.
Web site: www.atkinsonelectronics.com
REV 5/03
Distributed by: