8
OUTPUT
POWER
INPUT
95 96 98
A1 A2
RESET
③
SHOCK TIME knob
0.2-10sec
TEST
MON LED
①
START TIME knob
0.2-30sec
CT
②
CURRENT knob
OC LED
10. construction
Description
Two of three phases of the motor current are monitored by integral current transformers (External
current transformers are required for current more than 60 Amps).
The internal solid state circuitry compares the monitored motor (or load) currents with the preset
current level.
When motor current exceeds the preset trip current level, the “OC” LED illuminates and indicates that
an overload has been detected.
The relay will trip after the preset trip time (SHOCK TIME) and the “OC” LED remains illuminated
indicating an overload trip has occurred.
When the motor currents decrease, the relay reverts after one second.
If the motor current drops back down below the preset current level before the preset trip time delay
has elapsed, Shock Relay will return to normal condition.
MON lamp (green) shows monitor condition.
It is turned on under the normal monitor condition, and the relay turns off the lights while it is
outputted.
With the visual aid of the “OC” LED flashing when motor current becomes 100
％
of the preset current
actual load current can be determined without aid of an ammeter.
The TEST button provides the means of testing service-worthiness and integrity.
Since the Shock Relay has definite time characteristics, the start trip delay may be adjusted with a
minimum setting of 0.2 through a maximum of 10 seconds.
The trip time adjustment range is from 0.2 through 5 seconds. The relay may be used as an electronic
shear-pin by setting the SHOCK TIME to minimum.
If the Shock Relay trips, always investigate to determine the cause and correct prior to restarting.
T1
Motor speed
Shock Relay
trips
Motor current
Ampere
TIME
Preset
MOTOR
STOP
OVER LOAD
T1<T0
①
START TIME
③
SHOCK TIME
( T0 )
②
Current
Output
Relay
③
SHOCK TIME
( T0 )
OVER LOAD
T0<T2
T2
OC
Flicker
Continue
Flicker
A
A
A
A
ｕｔｏ
ｕｔｏ
ｕｔｏ
ｕｔｏ
R
R
R
R
ｅｓｅｔ
ｅｓｅｔ
ｅｓｅｔ
ｅｓｅｔ
after 1s
