How To Convert a MEP016D to 120/240 Volt Use

There is a lot of chit chat on the web about converting the MEP016D military diesel generator to dual/simultaneous 120/240 volt output. The normal output is either 100% 120 volt or 240 volt (both single phase), but not both.

Before going further, some disclosures:

  • GMG always recommends the hiring of a local licensed and insured electrician to help in any electrical work such as what this blog post discusses as well as wiring a generator to your home via a transfer switch.
  • GMG is in no way whatsoever responsible for any injury (to a person or machine).
  • Military generators purchased from the government are always assumed to be tinkered with and must be gone through with a certified generator technician. GMG inspects, repairs, refurbishes and tests all generators we sell. We can only warrant units that we sell.

Now for the blog post!

Step 1:  Open up your MEP016D or MEP016 control box and find the Phase Selector Switch. Make sure the unit is NOT running and is also fully grounded. Read notes on how to ground the generator.

Step 2:  Set the Phase Selector Switch to Single Phase 240 volt and then remove the knob so that it can’t be changed again. Tag the knob with a tag showing the date of this modification and a warning that this setting CAN NOT BE reset (i.e. the Phase Selector Switch is now non-usable and has been hardwired into one setting).

Step 3:  Place a piece of #10 copper wire from LO to TB-6. TB-6 is the closest terminal as you face the control panel and gauges. TB-1 is the furthest terminal from you facing the control panel and gauges.

Step 4: Make sure all connections are secure and that unit is grounded per manual.

Step 5:  Then, using a multi-meter, test the following on the output terminal studs after starting the unit and making sure the unit is outputting 60 Hz power (best to inspect the Hz meter as well as test the convenience outlet).

  • L1 + L2 should provide 240 volts
  • L1 + L0 should provide 120 volts
  • L2 + Lo should provide 120 volts

Step 6:  If any of the above is not correct, you must check all connections.  L1 and L2 are your hot legs. Lo is your neutral.

Step 7:  The black science of this is that you now need to balance the two 120 volt legs so that you don’t overload either leg. So on your breaker panel (ideally your transfer switch breaker panel), you must balance the draw from each of the hot legs so neither leg is overloaded.

3 thoughts on “How To Convert a MEP016D to 120/240 Volt Use

  1. gmg says:

    Unfortunately, your switch most like broke internally. There is no simple way to fix. You could attempt to investigate and dissect the phase selector switch, but that will not be simple or easy and must be done with care so as not to mismatch any wires.

  2. Dennis Blum says:

    I have a 5KW, MEP002A, NSN6115-00-465-1044. I turned the phase selector switch all to the left just to check it out. It was a little tough to turn. Now it wont turn back. I didn’t want to exert to much pressure to turn it back. I tried not to but exerted enough pressure and broke the switch knob. Is there some kind of release that I have to operate? I looked and couldn’t find one. I need to get it back strait up so I would have 240/120. I have replaced the knob but am afraid to try to turn it again. What do you suggest?

  3. wendel says:

    I follow you thru steps 1-3. About the ground in step 4. Could you elaborate further on grounded per manual. I own one of these units . Are manuels different from one to the other? What lug will need to be grounded.

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