Specifications
Replaceable Parts
Assembly and Disassembly Guidelines
Agilent E4418B/E4419B Service Guide 5-9
Removing the A1 Power Supply Assembly
1. Remove the power supply cover by lifting it out.
2. Disconnect the line input module from the chassis and power supply 
assembly.
3. Disconnect the cable assembly from the power supply which connects to the 
A2 processor assembly.
4. Unscrew the power supply assembly and lift out the power supply. (When 
replacing these screws use a 9 lb/in T15 screw driver.)
WARNING  When replacing the power supply unit in the power meter ensure that 
all earth wiring is reconnected. There are two terminals to check:
The first is the force fit connector to the power supply unit itself. It is 
essential that the gap between the terminal and the adjacent large 
capacitor is maximized. Fit the connector so that its flat side faces 
towards the large capacitor. 
The second, a closed loop terminal bonded to the chassis with an M3.5 
machine screw (use a 9 lb/in T15 screw driver). 
All the protective earth wiring can be identified by the insulation color 
green with a yellow stripe.
4402serv.book Page 9 Tuesday, October 14, 2003 3:18 PM










