Alpha Technologies USM2 - Manual (Page 19)

19
©2000 ™
704-587-B0-003 Rev.D
4.1 USM2 Input Signals and Controls
Definition of what is acceptable for HIGH and LOW signal levels used throughout the USM2:
HIGH is typically defined as AUX DC Voltage ± 10% (+5VDC, +15VDC, or +24VDC as set by configuration). Voltage
exceeding AUX DC is abnormal, but will not likely damage the USM2.
(90%AUX DC < HIGH < AUX DC)
LOW is typically defined as 0VDC, however any nonnegative voltage between 0VDC and +1VDC will be accepted by the
USM2 as LOW.
(0VDC < LOW < 1VDC)
USM Input Results:
Defines affect of USM2 inputs on the XM2.
Charger Control (pin 9)
LOW
XM2’s Battery Charger commanded to ‘Accept’ mode.
HIGH
XM2’s Battery Charger allowed to return to ‘Float’ mode
NOTE: Due to design improvements and changes the Charger Control function is no longer supported, however,
some “old” USM2 may still have this function.
Test/Reset Control (pin 11)
LOW
XM2 commanded to initiate a remote inverter test. Successful completion of an inverter test will reset / clear
a latched Equipment Fail Alarm.
HIGH
Inverter test command released, XM2 may exit test.
USM2 Input Legend:
LOW:
Status monitoring device pulls USM2 input to common (pin 1 and/or pin 12). (0VDC < LOW < 1VDC)
HIGH:
Status monitoring device opens connection, allowing input to be pulled up to Aux DC, or drives input high.
(4VDC < HIGH < AUX DC)
IMPORTANT NOTE: In order for the USM2 to function correctly, OUTPUT (N) must be grounded to the XM2’s chassis!
During normal operation this is automatically done though the SPI, but during bench testing this ground will
have to be manually maintained, by placing a jumper between the Output Neutral and chassis ground.
4. Signal Definitions