Hello, i am working or a circuit for a desk lamp and having some troubles with the transformer. First of all, when i bought my transformer, i had no idea that when it is submitted to a high current some voltage losses would appear... But the true problem is this:
The specs of the transformer are 500mA max current, 127VAC -> 15VAC. First, when i measure with no load, 16VAC are present on secondary and the rectified and filtered through a 2200uF eletrolytic cap is 23.05V. When i attach a load of 90mA, the secondary presents me with a 15.3VAC and the rectified and filtered through a 2200.... shows a 17.8V. That is really weird and it's happening with other transformers also, can someone explain this to me ? If the secondary has 15.3VAC the rectified should be at least 20.6V right ? Already accounting the bridge drop.
I tested a 200mA max current with the same step-down, when i submitted it to 100mA the drop was insane, 12.2VAC on the secondary and 13V on the rectified side!
It may be something newbish i am doing or asking.
The specs of the transformer are 500mA max current, 127VAC -> 15VAC. First, when i measure with no load, 16VAC are present on secondary and the rectified and filtered through a 2200uF eletrolytic cap is 23.05V. When i attach a load of 90mA, the secondary presents me with a 15.3VAC and the rectified and filtered through a 2200.... shows a 17.8V. That is really weird and it's happening with other transformers also, can someone explain this to me ? If the secondary has 15.3VAC the rectified should be at least 20.6V right ? Already accounting the bridge drop.
I tested a 200mA max current with the same step-down, when i submitted it to 100mA the drop was insane, 12.2VAC on the secondary and 13V on the rectified side!
It may be something newbish i am doing or asking.