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6.4 Computer Interface port
The Computer Interface port is diagramed below. Those with technical
abilities wishing to use this port in a special application should be aware of
the following limitations and capabilities of the interface.
■Outputs at Pins 3, 5, and 6 are open collector outputs which must be
pulled up to a common referenced supply no greater than +40 Vdc. The
transistors are capable of a maximum noninductive load of 25 mAdc. Use
only Pin 4 as the common.
■The output at Pin 2 generates a low-to-high RS-232 level upon transfer
of the output load to UPS battery power. The pin is normally at a low
RS-232 level.
■The UPS shuts down when a high RS-232 level is applied to Pin 1 for 4.5
seconds. The UPS responds to this signal, after a delay, only during on-
battery operation.
■An unregulated +24 Vdc appears at Pin 8 of the interface port whenever
the UPS is powered. The supply is limited to 40 mAdc maximum.
6.0 UPS Monitoring