User's Manual

20 Versus Technology, Inc.
To connect the sensors to the punch-down block:
For connecting the sensor wires to the punch-down block, refer to the Punch-down Block Organization
Chart for the location each wire should be connected on the block.
1. Remove all bridge clips from the punch-down block.
2. Referring to the Punch-down Block Organization List to make sure each sensor wire is
connected to the correct position on the punch-down block, connect the sensor wire-pairs to
the appropriate punch-down block pin-pair positions using the punch-down block tool.
3. Check isolation.
This is necessary because in the course of interconnecting many sensors to a collector, it is not
uncommon to make contact with a sharp metal edge, ganged knockout box, or electrical
ground with one of the conductors. It is critical, however, that such accidental connections be
located and cleared before applying power to the system. The effect of these accidental
connections can range from mild to severe. In many cases, erratic behavior may be noted. In
some cases, equipment damage may occur. In any case, an electrical code violation has
occurred.
To verify that the system is "isolated" from building and electrical grounds:
Note: It may be helpful to disconnect the collector from the punch-down block
while this measurement is made. This will isolate the sensor wiring completely.
1. Use an ohmmeter or multimeter set to the 2K (2000)-ohm scale.
2. Clip one probe to the nearest electrical conduit, electrical ground, or metal water
pipe.
3. Touch the other probe to each punch-down block row in turn.
4. Every row MUST indicate an infinite (open) connection. If this is not the case, the
suspect line must be traced to find the accidental connection to the structure that has
been made.
4. Once isolation has been checked, replace the bridge clips on the punch-down block.
4.5 Communication Room Check
There are several items that need to be verified before applying power to the system. Use the
Communication Room Checklist in section 6 to check off each step as it is completed.
4.5.1 Checking the Collector Wiring
A visual check of the collector wiring should find the punch-down block secure and the collector unit
connector firmly seated against the punch-down block connector. See the Collector Voltage
Troubleshooting Flow Chart in section 5 Troubleshooting Guide, for checking the collector wiring.
WARNING!
Correct two-pair wiring is essential. Crossed or reversed pairs can cause
equipment damage in some cases. Always test all wiring before connection
of system power sources.