NEWS | May 14, 2021

MEP-831A 3kW TQG: NSN Confusion Leads to Faulty Orders

Generator training
Dear Editor,

The MEP-831A 3kW tactical quiet generator (TQG) set, NSN 6115-01-285-3012, is covered in TM 9-6115-639-13&P (Aug 17). Before this publication, there was an error with the callouts for the 60Hz and 400Hz frequency converters in the RPSTL. It listed NSN 5895-01-477-0858 as the 60Hz frequency converter, when this NSN was actually for the 400Hz frequency converter.

The correct NSN for the 60Hz frequency converter was initially NSN 5895-01-477-0855, which has now been replaced by an upgraded model, NSN 5895-01-587-6582.

Both NSNs have been entered into an Interchangeable and Substitutability (I&S) relationship. An I&S relationship means that there is more than one NSN that can be used for the same purpose. In this case, NSN 5895-01-477-0855 was replaced by the newer NSN 5895-01-587-6582. They are now in a relationship where regardless of which one is ordered, both will bring the part you need. 

The problem is that requisitions are coming from the field for the 400Hz frequency converter, NSN 5895-01-477-0858, from DoDAACs that are not authorized a 400Hz TQG (MEP-832A, NSN 6115-01-287-2431).

Only the following units are authorized a 400Hz TQG (all LIN G74847):
WZ4AAA 203d MI Bn (Compo 3), APG, MD
W4G8AA C00VB6, W15P66, W15P7V, W37LY7, W56PHS, W56PHW, W58BW0, W58BXX, W58BXY, W81JF7, W81TK1, W900T9, W90282
US Army Communications-Electronics (Compo 1), AMC
W4GVAA CG0UTK, CG0UTU, W15GK8, W15GK9, W15R7S, W56MMV, W56NSF, W56RTN, W58H6M, W58H9U, W58VME, W800U6, W800U7, W8083U, W8087P, W80KHR, W80SLL, W80YBX, W81DJP, W81JF3, W81LN5, W90653, W906DE, W90AGF, W90FPJ, W90QKH, W90QKJ, W90TER, W90XKS, W90YZK, W910UV, W910Z0, W91UQA, W91YLJ, US Army Communications-Electronics (Compo 1), AMC
W4T3AA W582HJ, W900WA, W900XL, W900XM, Spec Ops Cmd, Central (Compo 1) DEF-S
WD78AA W806QL, W90T5V, W90T5Z W90T6D, 264th Engr Co (Compo 1), FORSCOM
WVK3AA W5047S, W569VT, W81ELU, W9082Z, 704th Engr Co (Compo 1), USARC
WBAVAA W56EKA, W583PU, W58G4Z, W90BQV, W90BQW, W90BR1, W90X6D, W90X6F, W90X6G, 95th Engr Co (Compo 1) USARPAC
WJP8AA W587GE, W90QWJ, Spec Trps Bn, 75th Ranger Regt (Compo 1) USARSOC
WH3LAA W33GG3, W502HA, W584JV, W80HYE, W81W1U. 1st Bn, 75th Ranger Regt (Compo 1) USARSOC
WH3MAA W587FY, W68PXK, W68SH9, and W81W14. 2nd Bn, 75th Ranger Regt (Compo 1) USARSOC
WJBLAA W587FZ, W804F2. 3rd Bn, 75th Ranger Regt (Compo 1) USARSOC
CECOM averages 2-6 orders per day from units that are not authorized a 400Hz TQG and find that the orders are “invalid.” When the order is rejected, the following note is added in the Outbound to Customer Block on the Purchase Request Document stating:
There had previously been an error in the TM for this item. The TM had stated this (NSN) is for the 60Hz application, but it is actually for the 400Hz sets. The 60Hz frequency converter is NSN 5895-01-587-6582. The TM was corrected in the last publication date of Aug 31, 2017. If you are using an older publication, please update your version. If you truly require the 400Hz frequency converter (NSN 5895-01-477-0858), please submit another requisition using advice code 2B.”

The field density for the 400Hz 3KW TQG is very low and “valid” orders for the 400Hz frequency converter, NSN 5895-01-477-0858, are less than 10 per year. CECOM believes that even though the TM corrected the error in its last publication, units must still be working from an older TM version.

Units with questions can contact me at:

Mr. Blair Mallonee
Editor’s note: We’re glad to spread the word worldwide.