HIKVISION DVR 4 Pin Power Supply - Which Side Is Negative / Which Side Is Positive?

[Raybold7]

Hi

I've got a Hikvision DS-7208HUHI-K1 and the power supply has failed. It's the 4 pin type.

I've ordered exactly the same charger but it has the 2.5mm plug so will need an adaptor similar to this https://www.amazon.co.uk/121AV-Adaptor-converters-Negative-Positive/dp/B07HMMRHL6

I didn't realise there were 2 options, i.e. positive and negative, I just thought it was an adaptor. Pictures show pins 2 and 4 as positive on one adaptor and 2 and 4 as negative on another adaptor.

Question I have is which adaptor do I need, positive on 2 and 4 or negative on 2 and 4.

I've asked a couple of CCTV companies but they didn't know. I've logged a ticket with Hikvision but they say it could take 7 days to respond.

Thanks

 

[JB1970]

Hi

I've got a Hikvision DS-7208HUHI-K1 and the power supply has failed. It's the 4 pin type.

I've ordered exactly the same charger but it has the 2.5mm plug so will need an adaptor similar to this https://www.amazon.co.uk/121AV-Adaptor-converters-Negative-Positive/dp/B07HMMRHL6

I didn't realise there were 2 options, i.e. positive and negative, I just thought it was an adaptor. Pictures show pins 2 and 4 as positive on one adaptor and 2 and 4 as negative on another adaptor.

Question I have is which adaptor do I need, positive on 2 and 4 or negative on 2 and 4.

I've asked a couple of CCTV companies but they didn't know. I've logged a ticket with Hikvision but they say it could take 7 days to respond.

Thanks

I had a similar issue a few weeks ago needing to swap the PSU on that same model. You don't actually need to know which pin is which:

• Cut the 2.5mm off the new supply.
• Using a test meter set to DC volts check polarity on the cable (a minus indicates your leads are reversed). In a single pair flat cable it's usually the wire that is striped or printed on that's positive but don't rely on that (see below fro the reason why)
• Cut the connector off the failed PSU leaving some wire to connect to the new cable
• On the failed PSU with the twin cable, unusually it is the striped wire that is negative and the plain wire that is positive. I know this as I had a lower rated power supply with the 4 pin DIN connector that was still working so I was able to test.

So just identify the positive wire on your new supply and connect to the solid black wire on the old cable, and connect the negative of the new supply to the striped wire on the old cable. You could use insulated bullet crimps, terminal block. I tend to strip back, twist, solder and insulate each wire individually then tape over/heat shrink the entire join.

You didn't necessarily need to get the same power supply. Any 12V DC supply with an output of 3.33 Amps or 40 Watts would suffice.

 

[Raybold7]

I had a similar issue a few weeks ago needing to swap the PSU on that same model. You don't actually need to know which pin is which:

• Cut the 2.5mm off the new supply.
• Using a test meter set to DC volts check polarity on the cable (a minus indicates your leads are reversed). In a single pair flat cable it's usually the wire that is striped or printed on that's positive but don't rely on that (see below fro the reason why)
• Cut the connector off the failed PSU leaving some wire to connect to the new cable
• On the failed PSU with the twin cable, unusually it is the striped wire that is negative and the plain wire that is positive. I know this as I had a lower rated power supply with the 4 pin DIN connector that was still working so I was able to test.

So just identify the positive wire on your new supply and connect to the solid black wire on the old cable, and connect the negative of the new supply to the striped wire on the old cable. You could use insulated bullet crimps, terminal block. I tend to strip back, twist, solder and insulate each wire individually then tape over/heat shrink the entire join.

You didn't necessarily need to get the same power supply. Any 12V DC supply with an output of 3.33 Amps or 40 Watts would suffice.

Thanks JB

Whilst not incompetent I’m not totally confident in carrying this out. I have the tools but I’m no electrician.

So I cut the wire, then what’s the setting on the test meter?

The reading being negative is simply a minus figure?

Then do the same on the new one and join the corresponding wires together.

Hadn’t thought of this but this helps thank you.

 

[JB1970]

So I cut the wire, then what’s the setting on the test meter?

The test meter is set to Volts DC. Once the 2.5mm plug is cut off on the new one you're measuring across the bare wires. Completely safe - it's 12V.

The reading being negative is simply a minus figure?

Correct. You put the meter leads across the two wires. Ensure the red and black lead are in the correct sockets on the meter. A minus reading shows that you have the leads connected across the wires reversed. When you see a standard reading without a "-" you know that the red meter lead is connected to positive and the black to negative.

Then do the same on the new one and join the corresponding wires together.

You've identified the polarity of the new one above. There's nothing to measure on the cut off DIN plug of the old failed PSU. The striped wire on the old one needs to connect to negative of your new supply and the plain wire to positive on the new supply. We know this as I've checked this on a working supply a couple of weeks ago.

If you're not confident with the above just buy a 2.5mm socket from Amazon; those have two marked terminals for + and -. Cut the DIN plug end off the old supply leaving enough length to work with and terminate the striped wire in "-" and the plain wire in "+" then just plug it onto the new PSU's 2.5mm connector.

 

[Raybold7]

I had a similar issue a few weeks ago needing to swap the PSU on that same model. You don't actually need to know which pin is which:

• Cut the 2.5mm off the new supply.
• Using a test meter set to DC volts check polarity on the cable (a minus indicates your leads are reversed). In a single pair flat cable it's usually the wire that is striped or printed on that's positive but don't rely on that (see below fro the reason why)
• Cut the connector off the failed PSU leaving some wire to connect to the new cable
• On the failed PSU with the twin cable, unusually it is the striped wire that is negative and the plain wire that is positive. I know this as I had a lower rated power supply with the 4 pin DIN connector that was still working so I was able to test.

So just identify the positive wire on your new supply and connect to the solid black wire on the old cable, and connect the negative of the new supply to the striped wire on the old cable. You could use insulated bullet crimps, terminal block. I tend to strip back, twist, solder and insulate each wire individually then tape over/heat shrink the entire join.

You didn't necessarily need to get the same power supply. Any 12V DC supply with an output of 3.33 Amps or 40 Watts would suffice.

Thanks JB

Whilst not incompetent I’m not totally confident in carrying this out. I have the tools but I’m no electrician.

So I cut the wire, then what’s the setting on the test meter?

The reading being negative is simply a minus figure?

Then do the same on the new one and join the corresponding wires together.

Hadn’t thought of this but this helps

The test meter is set to Volts DC. Once the 2.5mm plug is cut off on the new one you're measuring across the bare wires. Completely safe - it's 12V.

Correct. You put the meter leads across the two wires. Ensure the red and black lead are in the correct sockets on the meter. A minus reading shows that you have the leads connected across the wires reversed. When you see a standard reading without a "-" you know that the red meter lead is connected to positive and the black to negative.

You've identified the polarity of the new one above. There's nothing to measure on the cut off DIN plug of the old failed PSU. The striped wire on the old one needs to connect to negative of your new supply and the plain wire to positive on the new supply. We know this as I've checked this on a working supply a couple of weeks ago.

If you're not confident with the above just buy a 2.5mm socket from Amazon; those have two marked terminals for + and -. Cut the DIN plug end off the old supply leaving enough length to work with and terminate the striped wire in "-" and the plain wire in "+" then just plug it onto the new PSU's 2.5mm connector.

The new supply has come and I have cut the wire of the old supply. Unfortunately they are not striped wires inside; one of them is sheathed in white and the other is just wrapped around it, a little like aerial coaxial. How do I know which one is positive?

 

[Raybold7]

Thanks JB

Whilst not incompetent I’m not totally confident in carrying this out. I have the tools but I’m no electrician.

So I cut the wire, then what’s the setting on the test meter?

The reading being negative is simply a minus figure?

Then do the same on the new one and join the corresponding wires together.

Hadn’t thought of this but this helps

The new supply has come and I have cut the wire of the old supply. Unfortunately they are not striped wires inside; one of them is sheathed in white and the other is just wrapped around it, a little like aerial coaxial. How do I know which one is positive?

Just cut the new one and that's the same, do I assume unsheathed/exposed is the same on both and the insulated is the same on both?

 

[JB1970]

Unfortunately they are not striped wires inside; one of them is sheathed in white and the other is just wrapped around it, a little like aerial coaxial. How do I know which one is positive?

The bare wire is negative and the white insulated wire is positive. So just match them like for like.

 

[Raybold7]

The bare wire is negative and the white insulated wire is positive. So just match them like for like.

Thank you so much.

 

[Raybold7]

All back online and working perfectly now. Thank you so much for your help JB, really appreciate it.

 

[JB1970]

All back online and working perfectly now. Thank you so much for your help JB, really appreciate it.

No problem