Nautel NV40 Troubleshooting Manual

Also see for NV30: Operation and maintenance manual

Nautel NV40 Troubleshooting Manual Manual pdf 51 page image

NV40/NV30 Troubleshooting Manual Responding to alarmsIssue 3.2 2014-12-10 Page 1-43+12 V Power Supply ReplacementSee Figure 1.6 on page 1-42 and Figures MD-2 and MD-7 in the Mechanical Drawings section(Section 6) of this manual.1. Remove the lower back panel. Retain hardware and locate the suspect +12 V power supplymodule [U1 (A) or U2 (B)].2. Temporarily disconnect ac power from the suspect +12 V power supply module bydisconnecting the appropriate ac plug from the ac distribution assembly (A6). Disconnect P2from A6J2 for +12 V power supply module A (U1). Disconnect P5 from A6J6 for +12 Vpower supply module B (U2). The +12 V power supply module’s green lamp should turn off.Verify ac power has been disconnected from the +12 V power supply module by using adigital voltmeter to verify 0 V between the L and ground terminals and between the N andground terminals.3. Disconnect all wiring from the +12 V power supply module’s terminal block, noting thespecific destination of each wire.4. Using a 4 mm hex key (not provided), loosen the two M5 cap screws securing the +12 Vpower supply module to the transmitter. Remove the +12 V power supply module and itsmounting plate from the transmitter.5. Remove the two M4 screws that secure the +12 V power supply module to its mountingplate.6. Locate or obtain a replacement +12 V power supply module (Nautel Part # UG57). ReverseStep 1 and Step 5 to reinstall the new +12 V power supply module. If necessary, refer toSection 4, “Wiring/connector lists” on page 4-1 to locate wiring details.7. From the AUI’s System Review page, select Controller and view the +12V A or +12 V Bmeter, depending on which +12 V module was replaced. If necessary, adjust thepotentiometer on the rear of the +12 V module until the meter reading is 12.6 V.8. The transmitter should resume normal operation and the alarm should clear.WARNING:Lethal voltages exist inside the transmitter when the power is turnedon. Follow replacement instructions carefully to ensure safety formaintenance personnel during power supply replacement.