First you set Vout unloaded. Then you put a DMM in series 10A scale current measuring mode between plus out PSU and active load's red binding post. Black post directly connected to zero out PSU. You turn the active load's pot until you read 4A. You will not be able to measure & trim Vout for long before the little board sinks get very hot at such high constant current so beware. You could start with setting less test current like 1A. To see output cables Vdrop also measure Vout at load side.
Active load max. reach 1.5A and I guess enter protection mode and goes down. Could be the 1A fuse to protect the power transformer?
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Re:load 2 dummy was 12W rated I think? 1.5A at 20V is already 30W so you scared it off. More amps it can soak only on smaller Vout tests.
Thing is how your freshly made L-Adapter behaved. Did it show indifferent behavior up to 1.5A?
Thing is how your freshly made L-Adapter behaved. Did it show indifferent behavior up to 1.5A?
I think I need to change the fuse for the power tx, 240VAC (mains) / 120VA = 2 + 10% tx efficiency & multiply x 2 = 8.8A?
What, the primary AC fuse you mean? 1.5A-2A slow blow for 120VA 230VAC Tx.
120VA/230V=0.52A * 300% Slow Blow for inrush as recommended by major Fuse manufacturers for this class of mains transformers
Thanks, so the formulae isn't valid for EI core or others kind of txs?
Some people said add 10% for tx eficiency and x 2 the value, that's for EI and others txs?
Some people said add 10% for tx eficiency and x 2 the value, that's for EI and others txs?
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The fuse manufacturers in their recommendations don't specify transformers shape they just categorize by primary voltage and VA capability.
Up to 400VA for less than 600V primary voltage single phase transformers they say +300% their primary current for SLB fuse value.
Primary current is VA/VAC primary. From 500VA to 2kVA they relax the recommendation to +170%. For more huge they say +125%
Up to 400VA for less than 600V primary voltage single phase transformers they say +300% their primary current for SLB fuse value.
Primary current is VA/VAC primary. From 500VA to 2kVA they relax the recommendation to +170%. For more huge they say +125%
Your sentence make me doubt "for this class of mains transformers"
So can aply to all power txs, right?
So can aply to all power txs, right?