Bell 212
 

Can anyone tell me is it necessary to carry out paralleling check after the D.C.U.'s have been swapped or replaced.

Bell 212
 

D.C.U.'s, what are these? ALWAYS post helicopter-related matters in the 'Rotorheads' section where you'll more authoritative replies.

cjg...

Technically....you should actually perform an operational check of each separate affected DC system prior to any paralleling checks after replacing a DCU...

The M&O was never really clear on this...and if memory is correct it was actually dealt with in Vendor's manuals on DCU.

But straight up... yes...you need to parallel the DCU's if changed out...even if swapped...as the #1 and #2 systems are independent of each other....

w1

The answer is yes do it. Its easy but holding the screwdriver on the tiny adjustment screw with a slottted head is a skill. Refer to BHT212 MM 96-39. The DC electrics in general are from 96-24 on. Worth a read. PB

Yeah make sure the plastic insulating sleeve is in place around the test connections where you plug in your multimeter, if the positive probe of your meter shorts out to the case of the DCU it'll fry. This is especially hard on single bus machines since the extra relays are in the way of the number one DCU's probe ports. Don't forget the different voltage setting for cold weather operations.