GE D30 Instruction Manual page 60

WIRING
The operation of voltage and current monitors is reflected with the corresponding FlexLogic operands (
, and
# VOFF CONT OP # ION
monitor is breaker trip circuit integrity monitoring; a typical application of the current monitor is seal-in of the control
command.
See the Digital Elements section of chapter 5 for an example of how form-A and solid-state relay contacts can be applied
for breaker trip circuit integrity monitoring.
USE OF FORM-A AND SOLID-STATE RELAY OUTPUTS IN HIGH-IMPEDANCE CIRCUITS
For form-A and solid-state relay output contacts internally equipped with a voltage measuring circuit across
3
NOTE
the contact, the circuit has an impedance that can cause a problem when used in conjunction with external
high-input impedance monitoring equipment such as modern relay test set trigger circuits. These monitoring
circuits can continue to read the form-A contact as being closed after it has closed and subsequently opened,
when measured as an impedance.
The solution is to use the voltage measuring trigger input of the relay test set, and connect the form-A contact
through a voltage-dropping resistor to a DC voltage source. If the 48 V DC output of the power supply is used
as a source, a 500 Ω, 10 W resistor is appropriate. In this configuration, the voltage across either the form-A
contact or the resistor can be used to monitor the state of the output.
Where a tilde "~" symbol appears, substitute the slot position of the module. Where a number sign "#" appears,
substitute the contact number.
NOTE
Table 3-3: Contact input and output module assignments
~6A module
Terminal Output or
assignment input
~1 Form-A
~2 Form-A
~3 Form-C
~4 Form-C
~5a, ~5c 2 Inputs
~6a, ~6c 2 Inputs
~7a, ~7c 2 Inputs
~8a, ~8c 2 Inputs
~6E module
Terminal Output or
assignment input
~1 Form-C
~2 Form-C
~3 Form-C
3-14
) that can be used in protection, control, and alarm logic. The typical application of the voltage
Consider relay contacts unsafe to touch when the unit is energized. Death or serious injury can
result from touching live relay contacts.
When current monitoring is used to seal-in the form-A and solid-state relay contact outputs, give the
FlexLogic operand driving the contact output a reset delay of 10 ms to prevent damage of the output
contact (in situations when the element initiating the contact output is bouncing, at values in the
region of the pickup value).
~6B module
Terminal Output or
assignment input
~1 Form-A
~2 Form-A
~3 Form-C
~4 Form-C
~5 Form-C
~6 Form-C
~7a, ~7c 2 Inputs
~8a, ~8c 2 Inputs
~6F module
Terminal Output
assignment
~1 Fast Form-C
~2 Fast Form-C
~3 Fast Form-C
~6C module
Terminal Output
assignment
~1 Form-C
~2 Form-C
~3 Form-C
~4 Form-C
~5 Form-C
~6 Form-C
~7 Form-C
~8 Form-C
~6G module
Terminal Output or
assignment input
~1 Form-A
~2 Form-A
~3 Form-A
D30 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 3: INSTALLATION
,
CONT OP # VON CONT OP
~6D module
Terminal Output
assignment
~1a, ~1c 2 Inputs
~2a, ~2c 2 Inputs
~3a, ~3c 2 Inputs
~4a, ~4c 2 Inputs
~5a, ~5c 2 Inputs
~6a, ~6c 2 Inputs
~7a, ~7c 2 Inputs
~8a, ~8c 2 Inputs
~6H module
Terminal Output or
assignment input
~1 Form-A
~2 Form-A
~3 Form-A