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AWA battery eliminator issue
#4

Hi Rob, 


If you bought the board from AWA, they should have provided a schematic or some documentation. You could report this issue to them.

I can' find a 1N400H.  is it possible that it is a 1N4004?  If so, it should be acceptable.  A 1N3001 is not acceptable, as it has a PRV of only 50V.  A 1N4004 has a PRV of 400V so it is acceptable.  I always use 1N4007s for low current supplies.  If in doubt, you can likely get about 20 - 50 of these for about $5.00 via eBay, even from a US based seller.

The transformer secondary connections are interesting.  It seems that the secondary has 2 windings.  It appears that they are put in series and feeding a bridge rectifier.  The connections on the board for this transformer are numbered, likely for the specific transformer called for.  It is important that the correct wires go in the correct holes to get the windings in series and in phase.

With the transformer disconnected and the diodes in place, Check each diode with the DVM on the "---|<--" scale.  There should read about 0.5 (volt drop, this is not ohms) in one direction but infinite in the other direction.  With the meter on the KOhm Scale, check between pins 7 and 12 on the board.  There may be a relatively low resistance, but the resistance should increase, eventually into the 100K to 1 Meg or higher.  If it does not, then there is a short downstream of the diodes. Looking on the underside of the board, 7 and 12 go to the bridge, 8 and 11 connect the 2 secondaries in series.  Any mixup here will either buck the voltage (no voltage but harmless) or short across at least one secondary winding.

Good luck.

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55


Messages In This Thread
AWA battery eliminator issue - by Rob Quay - 01-21-2023, 09:43 PM
RE: AWA battery eliminator issue - by MrFixr55 - 01-22-2023, 01:28 AM
RE: AWA battery eliminator issue - by Rob Quay - 01-22-2023, 10:39 PM
RE: AWA battery eliminator issue - by MrFixr55 - 01-24-2023, 09:16 PM
RE: AWA battery eliminator issue - by Rob Quay - 01-25-2023, 04:28 PM
RE: AWA battery eliminator issue - by MrFixr55 - 01-25-2023, 08:46 PM
RE: AWA battery eliminator issue - by MrFixr55 - 01-25-2023, 09:46 PM
RE: AWA battery eliminator issue - by Rob Quay - 01-25-2023, 10:49 PM
RE: AWA battery eliminator issue - by MrFixr55 - 01-26-2023, 08:27 AM
RE: AWA battery eliminator issue - by Rob Quay - 01-26-2023, 09:52 AM
RE: AWA battery eliminator issue - by Rob Quay - 01-26-2023, 12:56 PM
RE: AWA battery eliminator issue - by MrFixr55 - 01-26-2023, 05:43 PM
RE: AWA battery eliminator issue - by radiorich - 01-27-2023, 02:02 AM
RE: AWA battery eliminator issue - by Rob Quay - 01-27-2023, 03:33 PM
RE: AWA battery eliminator issue - by MrFixr55 - 01-27-2023, 10:12 PM
RE: AWA battery eliminator issue - by radiorich - 01-27-2023, 10:22 PM



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