Monarch Instrument DC1250 User Manual
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2.5.2 Setting Alarms
Setting and configuration is done in the
The alarm setpoints are set in the same units as the input type and may be different for
each channel. When setting the actual setpoint value, the value may be incremented in
steps other than what is expected (unit steps). This is due to the fact that the input is
converted into a digital value with a finite resolution. It is not possible to set a setpoint
value that cannot be resolved by the internal microprocessor. Select the closest value
to the exact value you require; it will always be with 0.5%. The same applies when
setting the deadband.
Note that when configuring the alarms, there is no correlation between inputs, alarms
and relay outputs. These are user defined. Each alarm can be assigned to only one
input channel.
When setting up each alarm channel, the user should DISABLE the alarm so that
parameters may be changed WITHOUT AFFECTING THE RELAYS. This is done in the
ALARMS menu by selecting the ENABLE option so that no appears to the left of this
option. Once everything is set, select ENABLE once more to activate the alarm,
indicated by the presence of the . (Refer to Section on
When setting up alarms, you may get unexpected results from the relays if they are
enabled. Ensure there is nothing connected to the relays that could result in an
accident due to random closing of the relays during setup and always DISABLE the
alarm as described above. Make the changes and then re-enable the alarm.
There are many different ways the alarms can be set up. All the alarms can be
assigned to a single channel and may be of the same type giving for example a various
degrees of high warning and ultimately a high shutdown indication. Also, the relays may
be assigned to any combination of alarms. This would allow a single relay output to
indicate any alarm active. The combinations are endless.
2.5.3 Alarm Indication
There are three indications of alarm condition: the relay outputs, visual icons on the
display and audible alarm.
When an alarm is armed and functioning, it is indicated by a small "1", "2", "3" or "4" in
reverse video on the bottom left hand side of the graphic display. These status indicators
remain on as long as the alarm is enabled. If an alarm is triggered (in alarm condition), the
status indicator will blink and the internal beeper will sound. The beeper can be
permanently disabled from the Advanced Setup Menu -
- ALARMS - OFF.
The relays close on an alarm condition, assuming they have been set up correctly. The
relays can be set as fail-safe by reversing the logic of the alarms (Advanced Setup
Menu - RELAYS - FAILSAFE).