Download The Tenma Model 72-1084 ATX Power Supply Tester is designed to

ATX Computer
Power Supply Tester
Overview
The Tenma Model 72-1084 ATX Power Supply Tester is designed to provide fast convenient verification of proper operation of ATX
style computer power supplies. Connecting an ATX 20-pin connector to CON1 of this tester will provide immediate visual
indication of operation of the power supply. This tester also includes an analog voltage meter to verify correct voltage of the
+3.3V, +5V, and +12V pins on this connector. Three separate connectors also allow verification of proper output voltage on the
peripheral power, floppy drive power and +12V CPU power connectors.
Operation
Typically, ATX style power supplies are switched on/off from the motherboard. The Tenma ATX Power Supply Tester simulates
this command by placing a proper current load across Pin4 and Pin5 of the 20-pin ATX connector. When its rocker switch is
placed in the ON position, the power supplies cooling fan will engage, and the LED indicator, located in the tester rocker switch,
will light. This indicates that the power supply is functioning. In most cases, this level of pass/fail testing is all that is required.
In some circumstances where the supply is operational yet erratic behavior exists, it may be desirable to verify correct voltage of
the 3.3V, 5V and 12V outputs. The three position rotary switch and DC voltmeter panel allow easy verification of these voltages.
Additionally, the supply voltage to external peripherals such as DVD/CD ROM, floppy and hard drives may be tested. This tester
will verify these types of outputs on older type power supplies also.
Many low cost computer power supplies have one internal circuit for each of 3.3V, 5V and 12V voltages. In this case, all outputs
whether on the motherboard, the processor or a peripheral connector, of the same voltage, are internally tied together. In higher
quality supplies, these outputs are independent and isolated from each other. The Tenma #72-1084 ATX Power Supply Tester will
independently verify each of these outputs, including the both +12V outputs on the P4 processor connector.
Directions
General Pass/Fail Test
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Disconnect the computer power supply from the AC power source
Disconnect all IDE and other devices that are connected to the computer power supply
Disconnect the large 20-pin ATX connector from the motherboard
Set the rocker switch on the tester to the OFF position
Connect the 20-pin ATX connector, from the power supply, to the tester
Connect the computer power supply to an AC power source
Set the rocker switch on this tester to the ON position
If the LED on the rocker switch lights, the power supply is functioning
Testing Output Voltages
Caution
Simultaneously connecting to CON2, CON3 or CON4 could potentially damage the computer power supply
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The 20-pin ATX connector must remain inserted in CON1 to allow the tester to keep the computer power supply in the ON mode
Ensure that the slide switch, located in the center of the unit, is set to the CON1 (left most) position
Use the three position rotary switch to individually test each of the +3V, +5V and +12V outputs on the ATX connector
The panel meter should show the same voltage reading on the meter
If the meter displays voltage other than that indicated by the switch, the supply is not functioning properly
Move the center slide switch to the CON2/3/4 (right most) position
Insert the small floppy drive connector (typically used for 3-1/2” drives) into CON2
Toggle the rotary switch between the 5V and 12V position to verify both supply voltages on this connector. This test should be
performed independently for all connectors of this type
Remove the connector from CON2, and insert the peripheral connector in CON3
Toggle the rotary switch between the 5V and 12V position to verify both supply voltages on this connector. This test should be
performed independently for all connectors of this type
If the rotary switch is set to the 3.3V position when testing CON2 and CON3, the voltage will still be measured from the ATX
connector inserted into CON1
Remove the connector from CON3, and insert the CPU power connector into CON4
This connector provides two separate +12VDC supplies to the P4 processor on appropriate motherboards
The slide switch located just beneath the CON4 label allows these supplies to be independently tested
The only valid position of the rotary switch in this operation is 12V
Toggle the upper right slide switch between both positions to verify proper operation of these two supplies
Model #72-1082
Tenma Test Equipment
www.tenma.com
Test Specifications
This tester performs the following tests to the connectors shown below
CON1
Pin 2
Pin 3
Pin 4
Pin 5
Pin 8
Pin 10
Pin 14
Pin 15
Pin 17
Pin 20
ATX Style Connector
+3.3VDC
Common (–) ground
Resistive Load to Pin 5
Resistive Load to Pin 4
LED Power Indicator
+12VDC
Jumper to pin 15
Jumper to pin 14
Led Power Indicator
+5VDC
CON2
Pin 1
Pin 2
Pin 3
Pin 4
Floppy Drive Connector
+5VDC
Common (–) ground
Common (–) ground
+12VDC
CON3
Pin 1
Pin 2
Pin 3
Pin 4
Peripheral Connector
+12VDC
Common (–) ground
Common (–) ground
+5VDC
CON4
Pin 1
Pin 2
Pin 3
Pin 4
P4 Type CPU Power Connector
Common (–) ground
Common (–) ground
+12VDC
+12VDC
Model #72-1082
Tenma Test Equipment
www.tenma.com