Cummins/Onan NTA855 — Fuel Pump Control AC Connections (240 VAC / 120 VAC Conversion)
Installation · Day tank fuel pump controller
For the Cummins/Onan NTA855, from the Cummins/Onan service manual.
Applies to: Cummins/Onan DFAB, Cummins/Onan DFAC, Cummins/Onan DFBF, Cummins/Onan DFCB, Cummins/Onan DFCC, Cummins/Onan DFCE, Cummins/Onan NTA855, Cummins/Onan LTA10 engine, Cummins/Onan NT855 engine, Cummins/Onan NTA855 engine
Procedure
- To convert 240 VAC to 120 VAC: remove jumpers between TB1-6 and TB1-7; connect one between TB1-5 and TB1-6 and one between TB1-7 and TB1-8.
- Move selector switch S103 on the control PCB to the up position for 120 V.
- If equipped with a transformer, remove jumpers between H2 and H3; connect one between H1 and H3 and one between H2 and H4.
- To convert 120 VAC to 240 VAC: remove jumpers between TB1-5/TB1-6 and TB1-7/TB1-8; connect two jumpers between TB1-6 and TB1-7.
- Move selector switch S103 on the control PCB to the down position for 240 VAC.
- Attach a tag to the control box indicating the supply voltage.
- Terminals TB1-8 and TB1-5 are available for a 120 or 240 VAC electric fuel shutoff valve rated not more than 0.5 amps.
Tools required
- Jumpers Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Fuel shutoff valve rated not more than 0.5 amps
Full service-parts list: Cummins/Onan DFBF →, Cummins/Onan DFCC →, Cummins/Onan DFCE →
Source: Cummins/Onan service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.