Service manual

• Record the DMM reading in Table 2-1
Positive Polarity, LO to Chassis, Channels
• Send OPEN (@nn00) to the FET Multiplexer
4. Check Tree Leakage Current
• Send SCAN:PORT ABUS to the FET Multiplexer
• Send CLOS(@nn00) to the FET Multiplexer to close channel
00 and Tree A, where nn is the card number (typically 01)
• Send TRIG SGL to DMM
• Record the DMM reading in Table 2-1
Positive Polarity, LO to Chassis, Tree A
• Send OPEN (@nn00) to the FET Multiplexer
• Send CLOS(@nn15) to the FET Multiplexer to close channel
15 and Tree B
• Send TRIG SGL to DMM
• Record the DMM reading in Table 2-1
Positive Polarity, LO to Chassis, Tree B
• Send *RST to the FET Multiplexer
5. Change Polarity
• Turn power supply and mainframe power OFF
• Connect DMM, power supply, and resistor as shown in Figure
2-11
• Turn power supply and mainframe power ON
6. Repeat Steps 2 through 4
• Record all results in Table 2-1 as
Negative Polarity, LO to Chassis
2-18 Verification Tests