DMD1080, DMD1080-DC DC Input Alarm Trips
3
Spring Clip
Upper Mount
Lower Mount
Mounting to a DIN Rail
Install module vertically on a 35 mm DIN rail in a protective
enclosure away from heat sources.
Do not block air flow. Allow 1” (25 mm) above and below hous-
ing vents for air circulation.
Precautions
WARNING! Avoid shock hazards! Turn signal input, output, and
power off before connecting or disconnecting wiring, or remov-
ing or installing module.
Installation
1. Tilt front of module downward and position the lower mounts
and spring clips against the bottom edge of DIN rail.
2. Clip Lower Mount to bottom edge of DIN rail.
3. Push front of module upward until upper mount snaps into
place.
Removal
1. Push up on bottom back of module.
2. Tilt front of module downward to release upper mount from
top edge of DIN rail.
3.The module can now be removed from the DIN rail.
Setup and Calibration
The input ranges are factory calibrated and do not require
adjustment.
The Setpoint potentiometer allows the operator to adjust the
level at which the alarm is activated. This control is adjustable
from 0 to 100% of the input range.
The Deadband potentiometer allows the alarm trip and reset
window to be adjusted symmetrically about the setpoint from 1
to 100% of the span. This allows the operator to fine tune the
point at which the alarm trips and resets.
The deadband is typically used to prevent chattering of the
relays or false trips when the process signal is unstable or
changes rapidly.
To calibrate the alarm section, set the deadband control to the
minimum (counterclockwise).
Set the signal source to a reference that represents the desired
trip point.
Adjust the setpoint control to the point at which the relay chang-
es state form a non-alarm to an alarm condition. The deadband
will be 1.0% of span in this case.
If a larger amount of deadband is desired turn the deadband
potentiometer clockwise. The deadband is symmetrical about
the setpoint; both transition points will change as deadband is
increased.
Output Test Function
When the test button is depressed it will drive the relays to their
opposite state. This can be used as a diagnostic aid during initial
start-up or troubleshooting. When released, the relays will return
to their prior states.
Operation
The green input LED provides a visual indication that a signal
is being sensed by the input circuitry of the module. It also
indicates the input signal strength by changing in intensity as
the process changes from minimum to maximum.
If the LED fails to illuminate, or fails to change in intensity as
the process changes, check the module power or signal input
wiring. Note that it may be difficult to see the LEDs under bright
lighting conditions.
The bi-color alarm LED provides a visual indication of the alarm
status. In all configurations, a green LED indicates a non-alarm
condition and a red LED indicates an alarm condition.
In the normal mode of operation, the relay coil is energized in
a non-alarm condition and de-energized in an alarm condition.
This will create an alarm condition if the module loses power.
For a normal acting, non-latching configuration, the alarm will
activate when the input signal exceeds the setpoint (HI alarm) or
falls below the setpoint (LO alarm), then will automatically reset
when the alarm condition no longer exists.
For a reverse acting alarm, the relay coil is de-energized in a
non-alarm condition and energized in an alarm condition. The
alarm activates when the input signal exceeds the setpoint (HI
alarm) or falls below the setpoint (LO alarm), then automatically
resets when the alarm condition no longer exists.
When the latching mode is selected, it will be necessary to push
the functional test button or remove power from the module to
reset the alarm. The alarm will only reset if the alarm condition
no longer exists.
