Symmetricom 1000 User Manual

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Chapter 3 Installing the TimeProvider
Making Connections
62
 TimeProvider User’s Guide
097-58001-02 Revision G – April 2008
Figure 3-5.
 Power Terminal Connectors
Figure 3-6.
 Assembling the ETSI (Front Access) Power Connector
Expansion Panel
All connections to the Expansion Panel, including power, are made using the 
interconnection cable, part number 060-58002-03.
Verifying Power and Grounding Connections
To verify power and grounding connections:
1. Using a DVM, measure the voltage between pins 1 and 2 on the rear access 
(NEBS) connector or between pins 2 and 3 of the front access (ETSI) connector.
2. Verify that voltage is –36 to –72 V DC. The inputs are protected against reverse 
polarity.
Pin 1: -48 V DC Battery
Pin 2: -48 V DC RTN
Rear Access Shelf
Front Access Shelf
Pin 1: Frame ground
Pin 2: -48 V DC negative lead
Pin 3: Return