Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: BIGWING on March 06, 2012, 10:25:00 AM
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just bought a second hand multi output power supply from ebay
but there is quite a bit of difference between req'd output and
actual measured
req'd voltage (dc) actual measured voltage (dc)
+12v +14.06v
+12v +13.79v
+24v +27.8v
+50v +48.5v
-12v -13.7v
+5v +5.2v
will this level of overvoltage damage breakout boards etc?
what is the normal tolerance on power supplies
cheers George
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Are you checking the voltages with a load on the outputs? It will likely fall down nearer to specs when there is a load.
Hood
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Hi Hood
no I was just testing across terminals?
the power outputs are
+12v @ 12A
-12v @ 2A
+24v @ 3A
+50v @ 10A
+5v @ 3A
what would you recommend for a load to test?
(sorry for basic question but not electrical)
cheers G
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What you have is clearly an unregulated supply, which will reach the rated voltage only at, or near, full load. Most electronic devices are spec'd at +/- either 5% or 10% on supply voltage, and you are well over that on all but the 5V output. In particular, most ICs are spec'd for no more than +/-10%, and are VERY likely to be damaged if this is exceeded. I would not use that supply to directly power any electronics, without knowing that they can tolerate the over-voltage.
Either get another supply, or add regulators to that one (and this is not really practical, or cost-effective at those current levels....).
Regards,
Ray L.
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Ok many thanks for the help
George
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can someone tell me
is a linear power supply the same as a regulated power supply
cheers G
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"is a linear power supply the same as a regulated power supply" - absolutely not. A regulated supply may, or may not, be linear, and a linear supply may, or may not, be regulated. "Linear" indicates it is not a switching power supply, but says nothing about whether or not it is regulated.
Regards,
Ray L.