GE DBT, Instruction Manual

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RELAY SETTINGS
GEK-105597C DBT Digital Trip Coil Supervision Relay 17
6.5 COIL RESISTANCE SETTING
This is the coil failure circuit threshold. It is a block of 4 dip switches.
The minimum value is 75
Ω
, the maximum 300
Ω
and the step 15
Ω
.
For example, if a setting of 150
Ω
is required, put dip switches 1 and 3 in the UP position. You then have: 75
+ 15 + 60 = 150.
The DBT will consider that there is a fault condition if BOTH resistances measured in 52a and 52b inputs are
OVER the setting. It also will consider a fault when both resistances are BELOW the setting, because this is not a
normal condition.
The fault has to be maintained during the set time to allow the output relay operate. This time prevents
misoperation during breaker status transition.
6.6 VOLTAGE SETTING
This is the threshold for the breaker power supply failure unit. As in the case of the resistance setting, it is a
block of 4 dip switches.
For the 110/125 V DC model the minimum value is 50 V, the maximum 125 V and the step 5 V.
For the 220/250 V DC model the values are double the above, so the minimum is 100 V, the maximum 250 V
and the step 10 V.
If a setting of 115 V is required (110/125 model), raise dip switches 1, 3 and 4, making a total of: 50 + 5 + 20
+ 40 = 115. This is equivalent to 230 V on the 220/250 V model.
6.7 TIME DELAY SETTING ADJUSTMENT
This is the timer adjustment, made through a block of 3 dip switches.
The minimum value is 0.2 seconds, the maximum 20 and the step 0.1.
Note: although it is theoretically possible to select a time which is higher than the maximum (for example, if
all the dip switches are put in the UP position you apparently have a setting of 27.5 seconds, the maximum),
in reality, if all the dip switches are in the UP position the setting is 20 seconds. Therefore, any adjustment
above 20 seconds will be considered as if it were 20 seconds. This has been done because there is no point
in having a higher setting.