Precision Digital PD6400 - Manual (Page 48)

Model PD6400 High Voltage & Current Meter Instruction Manual
48
Programming Set and Reset Points
High alarm indication: program set point above reset point.
Low alarm indication: program set point below reset point.
The deadband is determined by the difference between set and reset
points. Minimum deadband is one display count. If the set and reset
points are programmed with the same value, the relay will reset one
count below the set point.
Note: Changes are not saved until the reset point has been accepted.
Setting Fail-Safe Operation
In fail-safe mode of operation, the relay coil is energized when the
process variable is within safe limits and the relay coil is de-energized
when the alarm condition exists. The fail-safe operation is set
independently for each relay. Select on to enable or select off to
disable fail-safe operation.
Programming Time Delay
The On and Off time delays may be programmed for each relay
between 0 and 999.9 seconds. The relays will transfer only after the
condition has been maintained for the corresponding time delay.
The On time delay is associated with the set point.
The Off time delay is associated with the reset point.
Relay Action for Loss of Input (Loop Break)
The loop break feature is associated with the current or voltage input.
Each relay may be programmed to go to one of the following conditions
when the meter detects the loss of the input signal (i.e. < 25 mA):
1. Turn On (Go to alarm condition)
2. Turn Off (Go to non-alarm condition)
3. Ignore (Processed as a low signal condition)
Note: This is not a true loop break condition; if the signal drops below 25
mA, it is interpreted as a “loop break” condition.