IMI66–107
2.16 Checking The System Installation
The system operating features are set to default conditions at initial power-up. These conditions
provide a basic operating system with a known set of parameters, and you should check out the
system with the default conditions in place. At any time while the system is operating, you can
reset default conditions from station port 10 or 12 following the instructions provided in chapter
3, Programming.
2.16.1
Checking The Resistance
Measure the resistance at the station connector blocks under the following conditions.
• AC power cord disconnected from electrical outlet.
• Common equipment connected to station connector blocks.
• Stations wired and wiring punched down on blocks.
• Bridging clips removed from blocks to isolate stations from common equipment.
Measure the resistance of each installed station and wiring from the station side of the connector
blocks. Resistance values will vary with cable length and station type but should be within the
following limits:
• Greater than 700 KΩ
2.16.2
Checking The Voltage
Make the following voltage measurements at the station connector blocks under the following
conditions:
• Bridging clips installed
• AC power connected to the common equipment
Measure the voltage across the signal pair. The measured voltage must be within the following
limits:
• 28–36 VDC
Digital Telephone System
Installing The DSU 2 – 51