Manual
4. Signal Definitions
18
704-683-B0-004, Rev. D
4.1 USM2.5 Signal Definition,
continued
Name: Tamper Switch Status
Pin: J4-7
Signal Type: USM2.5 Discrete Output
Referenced to: Common (J4-1, J4-12)
Description: USM2.5 output indicates the current state of the XM2’s enclosure
tamper switch. This is a non-latching type alarm.
Active Means: The enclosure door is opened or the tamper switch is
disconnected.
Active State: HIGH
Inactive Means: The enclosure tamper switch is properly connected and the door
is closed.
Inactive State: LOW
How to Test: Disconnect any tamper switch from the USM2.5 TMPR
connector. Short USM2.5 TMPR connector; the USM2.5 tamper
status (pin #7) should go LOW. Remove the short on USM2.5
TMPR connector (open circuit) and the Tamper Status output
should go HIGH.
NOTE: The tamper output polarity can be switched using SW1-7
Name: Output Current #1
Pin: J4-8 (J4-13 for ONU equipped units)
Signal Type: USM2.5 Analog Output #1
Referenced to: Common (J4-1, J4-12)
Description: This USM2.5 analog output is a DC approximation of the total
XM2 AC output #1 current.
Parameters: 0.4VDC per AC ampere XM2 output.
How to Test: Verify voltage on J4-8 is 0.4VDC per AC ampere XM2 output #1.
(± 5% tolerance)
NOTE: The output current scale is dependant upon SW1-3
Name: AC Input Voltage (formerly not used on USM2 cards)
Pin: J4-9
Signal Type: USM2.5 Analog Input
Referenced to: Common (J4-1, J4-12)
Parameters: This analog output should be 0.0211 VRMS per VAC output for
120 VAC systems or 0.0113 VRMS per VAC output for 240 VAC
systems. (Approx. 2.5 VAC.)
How to Test: Verify that the voltage on J4 pin 9 is .0211 VRMS or .0113 VRMS per VAC
of the XM2’s input voltage (true RMS voltmeter must be used to read this
signal). (Approx. 2.7 VAC.)