Issue:
Replacement for obsolete switch QMB3640
Product Line:
QMB panelboard, switchboard with QMB distribution.
Environment:
Products sold in North America
Resolution:
The replacement depends on the existing busbar design inside the QMB panel or Switchboard. There are three designs, round, flat and railroad track like.
There is no longer a fusible switch replacement for a QMB3640, 400A QMB Series 4 switch for the QMB panel with round busbars.
However, if the panel has flat busbars, we do have a QMB3400LA circuit breaker unit and the QMB310EX plug-on extension assembly, is also required in order to mount the breaker unit.
If the panel has the railroad track looking busbars, the replacement would just be the QMB3400LA.
When replacing the QMB3640 you may need filler plates but they are obsolete, no longer available, with no replacement. Suggest installer to have fabrication done at a local sheet metal shop.