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CM9760-REL PROPERTIES EXPOSED FOR SCRIPTS AND EXPRESSIONS
The following table lists CM9760-REL relay interface unit properties that can be used in scripts and expressions.

Changing the State of a Relay Point

An operator can change the state of a relay point by working within the CM9760-REL relay unit’s Device Control dialog box in the client (refer to
the Client Operation Manual for instructions). However, you may want to allow an operator to change the state of a relay point without opening
the Device Control dialog box. VMX300(-E) provides the following methods:
•Global Script: Write a global script that changes the state of the specific relay point. Give the operator permission to run the global script
and permission to control the relay unit. This method is useful when you do not want to give the operator permission to access the relay
unit’s Device Control dialog box. Refer to the Global Scripts section for instructions on writing a global script. Refer to the User Groups
section for instructions on assigning operator permissions.
•Label or Hotlink: Create a label or hotlink that sets the state of a specific relay point and give the operator permission to control the relay
unit. This allows the operator to quickly change the state of a frequently accessed relay point, without having to open the Device Control
dialog box. Refer to the Hotlinks and Labels sections for instructions on creating labels and hotlinks. Refer to the User Groups section for
instructions on assigning operator permissions.

Defining Normally Open and Normally Closed Relay Outputs

Relay outputs are commonly wired as normally open (N.O.), so that if the contact wires close, the relay action is triggered. When the relay is
triggered, the relay state corresponds to “True” in VMX300(-E), whereas “False” corresponds to the normal (N.O.) state of the output. For
example, if the relay action is to turn on a VCR, “True” equals “On” and “False” equals “Off.”
When a relay is wired as normally closed (N.C.), the relay state still corresponds to “True” in VMX300(-E), and “False” still corresponds to the
normal state, which is N.C. in this case.
When you define an expression in the server configuration using the relay outputs, the expression tests whether the point is “True,” regardless of
whether the actual relay output is wired as N.O. or N.C., as shown in the following table.
Table AG. CM9760-REL Properties and Values
TYPE OF
PROPERTY PROPERTY VALUE INDICATES
Read Status CommLoss The device driver cannot communicate with the device.
Normal The device is in its normal state.
Unknown The communications status between the device driver and the device cannot be
determined.
Alarm True The relay unit is currently in an alarm state.
False The relay unit is not in an alarm state.
Point_iii True The relay output numbered iii is True.*
False The relay output numbered iii is False.*
Write Alarm True Set Alarm to True to indicate the CM9760-REL is in an alarm state. CM9760-REL icons
flash in the alarm colors when Alarm is set to True.
False Set Alarm to False to indicate the CM9760-REL is not in an alarm state.
Point_iii True Set Point_iii to True. Example: SET Relay_Unit_01.Point_001 = True
False Set Point_iii to False. Example: SET Relay_Unit_01.Point_001 = False
*Note that “iii” equals the relay output number, which can range from 001 to the maximum number available on the relay units (the maximum
number for one relay unit is 64; with two daisy-chained relay units the maximum number is 128, and so on).
Table AH. Defining Normally Open and Normally Closed Relay Outputs
State of Contact N.O. N.C.
Open False True
Closed True False