DPM3 User Manual, 1st Edition
User Manual - DPM3 Series Panel Meters
28
Output Options
All options are optoisolated with respect to input signal and power supply.
Relay Configuration
Introduction
Some DPM3 models are equipped with either 2 or 4 relays that can provide individual alarm
and control capabilities. All relays can be configured to function based on independent setpoint
values within the full configured display range, time delay (in seconds), hysteresis (in counts of
display) and selectable HI/LO acting.
Description of Operation
The relay outputs activate when the display value reaches the corresponding programmed relay
setpoint value. The following relay operational parameters must also be set:
a. COMPARISON NET/ GROSS
In “NET” mode will compare the setpoint value with the display net value. In “GROSS” mode,
the comparison will be with the sum net + tare.
b. HI/ LO ACTING MODE.
In HI mode, the output activates when the display value exceeds the setpoint level and in LO
mode, the output activates when the display value falls below the setpoint
c. RELAYS CONTACT DEFAULT STATE NO/NC.
Defines relays contact status by default: “NO” (normally open) or “NC” (normally closed).
NC status can be used as a FAIL SAFE function, allowing the power supply or device failure
detection sending a signal to the PLC or main monitoring system.
d. PROGRAMMABLE TIME DELAY or HYSTERESIS.
Each output action can be deferred by a programmable time delay or hysteresis level.
The time delay is the time that takes the output to activate after passing through the setpoint in
the up or down direction, while the hysteresis band will be selected asymmetrical i.e. only acts
on the output deactivation edge. The delay is programmable in seconds, from 0 to 99.
The hysteresis can be programmed, in counts, within the full display range. The decimal point
appears in the same position as programmed in the display configuration module.
The figures 1 and 2 show the time delay action (dly) and the hysteresis action (hys) of two
alarms (SET1 and SET2) programmed to activate in HI mode (OUT1) and LO mode (OUT2)
