There is a piece of test equipment called an Electronic Load, basically it is a programmable constant current source with lots of fans.
You could always get lots of resistors, around 10-15W resistors X20 should do it.
Or you could make a quick and dirty electronic load with a bank of transitors on a heat sink.
This weekend Harbor Freight has a 12V battery load tester on sale for something like $12.99. I haven't looked at it but if it's like most normal battery testers it will have a simple ammeter movement included, although the scale may only be good/?/bad but easy enough to interpret.we want to test the load of 12 v DC supply , up to what maximum current limit it can deliver to load , any good load tester can you suggest ?
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