I have a PC power supply I am using as Bench power supply that gives me 12,5,3.3 V. I am attaching to it the LCD display See attachment.
I am facing a very confusing situation and I need you to explain the behaviour. The five wires from the display are in two groups. One group to supply the power for the display ( thin Black and Red) the other to connect to the PC power supply to display the voltage and current of one of its outlets (3 outlets 3.3,5, 12)
( Two Thick Red and Black and a yellow wire). And here is the key to the problem:
I decided to use the 12 V outlet to provide the needed power for the display. ( Instead for a SEPERATE power supply . a battery , to power it)
Made the connects as shown in the attachment ( very important to see), Here is the weird thing :
1. The Display is OK
2. When I connect as suggested, I get SHORT CIRCUIT !!!!
3. I floated the THICK black and the SHORT CIRCUIT is GONE , but I do not get current reading!!!!! and the voltage is displayed correctly.
4. If I ground the THICK BLACK wire to the casing of the power supply I get VERY HIGH reading for current NOT TRUE. ( The load is in ma's )
I have tried to x-ray the situation for you to SEE what is going on ; if I failed please ask me to further explain the situation.
P.S. The display is working perfectly, I tested it before AND after in a seperate circuit.
Your input will be greatly appreciated
I am facing a very confusing situation and I need you to explain the behaviour. The five wires from the display are in two groups. One group to supply the power for the display ( thin Black and Red) the other to connect to the PC power supply to display the voltage and current of one of its outlets (3 outlets 3.3,5, 12)
( Two Thick Red and Black and a yellow wire). And here is the key to the problem:
I decided to use the 12 V outlet to provide the needed power for the display. ( Instead for a SEPERATE power supply . a battery , to power it)
Made the connects as shown in the attachment ( very important to see), Here is the weird thing :
1. The Display is OK
2. When I connect as suggested, I get SHORT CIRCUIT !!!!
3. I floated the THICK black and the SHORT CIRCUIT is GONE , but I do not get current reading!!!!! and the voltage is displayed correctly.
4. If I ground the THICK BLACK wire to the casing of the power supply I get VERY HIGH reading for current NOT TRUE. ( The load is in ma's )
I have tried to x-ray the situation for you to SEE what is going on ; if I failed please ask me to further explain the situation.
P.S. The display is working perfectly, I tested it before AND after in a seperate circuit.
Your input will be greatly appreciated
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