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> 20/24 pin atx power supply test fixture with amp shunts
20/24 pin atx power supply test fixture with amp shunts
24 Pin Din Rail Assy with 4 20AMP 200mV Shunts
(Din Rail Mounts shown in photo but not included in this model - see 400088-dr or just ask us)
This adapter allows you to connect a 20 pin or 24 pin ATX power supply to actually test the ATX power supply with the required specied load.
Each voltage output is monitored by a current shunt for measuring the current. Testing a power supply without a load is really not testing it at all.
Most power supplies even require a minimum load when operated. This minimum load is not complyed with by the other ATX tester.
Lighting an LED is not a sufficent load for testing the voltage output range and current draws.
Quite often you will find the the voltage is out of spec until the minimum required load is meet.
Each of the 4 Voltge output has a .01 ohm 1% 2 watt shunt resistor
The voltage drop accross these 4 shunts can be measured with most digital DVMs in the mVolt scale at the 1 x 8 screw terminal.
The larger screw terminals are mark with there respective Voltage output.
A dummy resistive load should be attached to provide the required load for testing.
To turn all ATX power supplies on you are required to jumper /PS_ON to ground.
That is why the jumper is in the picture. Without the jumper the power supply is off. This can also be attached to a switch for hand control.
Qty 4 standoff and screws are included for panel mounting or desktop use
The PCB assy can also be din rail mounted ...order the DR-version (400088-dr as shown in photo but not included in this model)
This adapter was originally designed to allow a High power computer grade ATX power supply to be used in Test Fixtures.
Computer Grade high wattage power supplies can be expensive but the PC industry has made them an affordable commodity.
Example using a Fluke 77 Multimeter
Meter is set for millivolts 10mV = 1 amp
10 v thru a 10 ohm = 1 amp
