DPM-100 Digital Panel Meter Modbus
®
Display
Instruction Manual
39
Setting the Relay Action (
act 1
)
Operation of the relays is programmed in the
Action
menu. The relays may be set up for any of the
following modes of operation:
1. Automatic reset (non-latching)
2. Aut manual reset at any time (non-
latching)
3. Latching (manual reset only, at any time)
4. Latching with Clear (manual reset only after
alarm condition has cleared)
5. Pump alternation control (automatic reset
only)
6. Sampling (the relay is activated for a user-
specified time)
7. Off (relay state controlled by Interlock
feature)
The following graphic shows relay 1 action setup;
relay 2-8 are set up in a similar fashion.
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 defined as 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
(
failsf
)
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 (
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 Communications
Break (
break
)
The Scanner will poll the slave device three times
before reporting a communications break condition.
After the third failure, the Response Timeout timer
starts and will determine the actual time to report a
PV in break condition.
1. Turn
On
(Go to alarm condition)
2. Turn
Off
(Go to non-alarm condition)
3. No Action (The relays will maintain the last
condition)
Refer to
Relay Operation After Communications
for details.
