Orban OPTIMOD-FM 8600, Operating Manual

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2-4
INSTALLATION ORBAN MODEL 8600
Figure 2-2: Wiring the 25-pin Remote Interface Connector
6. Connect tally outputs (optional)
See the schematic on page 6-42.
There are two tally outputs, which are NPN open-collector and operate with re-
spect to pin 1 (common). Therefore, the voltage applied to the load (such as a re-
lay or optoisolator) must be positive. You can use the 12 VDC source on pin 25 to
drive the high side of the load, taking into account the fact that the voltage on
pin 25 is current limited by a 310
Ω
resistor.
The tally outputs are protected against reverse polarity.
I
To avoid damaging the 8600, limit the current into a tally output to
30 mA. DO NOT connect a tally output directly to a low-impedance
voltage source! The tally outputs are not protected against this
abuse and Q3 or Q4 is likely to burn out.
Note that the tally outputs have no special RFI protection. Therefore, it is wise to
use shielded cable to make connections to them.
See Tally Output Programming on page 2-62 for instructions on using the tally
outputs.