DAHUA PoE camera does not power with Poe switch but powers with 12v adapter

In my case, the POE switch, the camera POE circuit and even the ethernet cable were faulty.
If your current POE source is OK as well as your Ethernet cable, then all you need is a POE splitter at the camera end to provide external power to the 3.5mm plug on the camera.

If your POE source is faulty and you need a new injector, then it should not be hard to find one that will work for that camera. I read the SD59225 requires up to 22Watts using 24V DC. (NOT AC).
 
There is no external power plug on wire harness. Only bare wires for rs485 connections with RJ45 ethernet jack. The spec sheet calls for 24VAC, and I can power up with variac.
Cannot power up with PoE+ only. Attached is spec sheet.
Page 3 of your specs show the 24VAC @ 3A power supply below. I'd PM Andy Wong @EMPIRETECANDY and ask about it's availablity and price.

dahua-24VAC-3A-power-supply.jpg
 
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I was referring to the spec sheet of the DH-SD59225 which is the camera you said you had. Its spec states a 24 VDC/2.5A power requirement. The spec sheet you attached is for the Pro Series 59230UNI which does list AC24V/3A as well as the power supply accessory TonyR showed. There was no power supply accessory listed for the 59225.
 
I stand corrected. sorry for the poor communication. My cam is SD59225U-HNI. Part numbering is so complicated.
I can obtain an external source but the fix would require another long cable run to the cam. Trying to avoid this, and get the PoE+ circuit repaired.
working on circuit, I suspect T1 xformer is shorted primary.
 

According to the link above, you need 24VDC, not 24VAC. FInd any PoE splitter, 23W minimum, lots of them on Amazon, of various quality and reliability.

If ethernet data is working, it is passing thru the T1transformer, not likely shorted. See my circuit sketch above. You need to look for diodes, MB8S or similar and look for power on the in & out, should be around 48VDC.
 
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I have the Pro series SD59225U-HNI, which included external power supply AC24v/3A. Purchased in 2017. I looked at your schematic, the design is for external DC supply.
The cam will only power on with external supply. PoE+ switch will not power cam on. I did borrow a PoE++ switch, and cam powers on.
 

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There are 3 common ways for PoE to power a device, Mode A (power on pins 1, 2, 3 & 6), Mode B (power over pins 4, 5, 7 & 8) and 8 wire (all 8 pins get used, this is for PoE++ 802.3bt).

If it works over PoE++, then you just need to determine which mode has failed and find a PoE injector that uses the other mode or just use a PoE++ injector/switch.

Sounds like one of the Modes have failed - could be a blown rectifier MB8S. Probe the inputs (~) and the outputs (+/-) and you should see 48V-ish on each end.

You probably won't find any PoE Splitters that will output AC voltage, since PoE is DC and making AC from DC requires a bunch of circuitry, and devices that do this will make 120VAC, not 24V.
 
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Thanks for your help. On my circuit board, the network Xformer is a Group-Tek HST-0041 SAR. I checked both MB6S and appear to be ok (ohm chk).
I could scope out the ethernet signals, but without power-up not much info. ordered new components, will shotgun repair.
 
My IPC 4631C-A worked only in 12V power line. When I measure capacitor with a multimeter, capacity was about 140 uf. After changed 220uf capacitor in poe board it's have a new life on poe line supply. Maybe this will be help someone.
 

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Am also experiencing similar situation but here all cameras not displaying on nvr . My Dahua 32 channel nvr not powering the cameras when connected directly to the nvr ,also when connected to external poe Netgear switch ,the cameras power but will not display on the nvr monitor but showing cameras are unable to connect to network host even after resetting the nvr to default. Any assistance from anyone.
 
Am also experiencing similar situation but here all cameras not displaying on nvr . My Dahua 32 channel nvr not powering the cameras when connected directly to the nvr ,also when connected to external poe Netgear switch ,the cameras power but will not display on the nvr monitor but showing cameras are unable to connect to network host even after resetting the nvr to default. Any assistance from anyone.
You need to assign a unique, static IP to each camera, in the same subnet as the NVR's LAN, but outside of the router's DHCP pool (if there is a router). I'd make the NVR's LAN IP static as well.
 
tha
You need to assign a unique, static IP to each camera, in the same subnet as the NVR's LAN, but outside of the router's DHCP pool (if there is a router). I'd make the NVR's LAN IP static as well.
Thank you Tony for your fast reply ,will try this you said . Although i have set up the installation two years ago as a new installation ,only for this month almost after two years of operation this issue and error message came up on all cameras and the NVR is not sending power to all cameras attached to it even after doing a cold reset .I had to move the cameras to a POE Netgear switch to power the cameras but still no picture display on the monitor. No live view display on monitor . poe showing red as a sign on all cameras even though they were all powered with the external poe switch
 
tha

Thank you Tony for your fast reply ,will try this you said . Although i have set up the installation two years ago as a new installation ,only for this month almost after two years of operation this issue and error message came up on all cameras and the NVR is not sending power to all cameras attached to it even after doing a cold reset .I had to move the cameras to a POE Netgear switch to power the cameras but still no picture display on the monitor. No live view display on monitor . poe showing red as a sign on all cameras even though they were all powered with the external poe switch
though i will need to assign a new IP address to all cameras ,since they are still on the default 10.1.1--- default IP from the NVR
 
tha

Thank you Tony for your fast reply ,will try this you said . Although i have set up the installation two years ago as a new installation ,only for this month almost after two years of operation this issue and error message came up on all cameras and the NVR is not sending power to all cameras attached to it even after doing a cold reset .I had to move the cameras to a POE Netgear switch to power the cameras but still no picture display on the monitor. No live view display on monitor . poe showing red as a sign on all cameras even though they were all powered with the external poe switch
First, you will likely need to disable the NVR's private server mode such as "plug 'n play".
I would then assign the NVR a unique static LAN IP and then add the "new" cameras manually, one at a time.
 
though i will need to assign a new IP address to all cameras ,since they are still on the default 10.1.1--- default IP from the NVR
Yes, that IP range is indicative of the NVR's private server when using POE; it's a different subnet from the NVR's LAN.
You should have the cams and the NVR's LAN on a 192.X.X.X subnet if using an external POE switch .
 
First, you will likely need to disable the NVR's private server mode such as "plug 'n play".
I would then assign the NVR a unique static LAN IP and then add the "new" cameras manually, one at a time.
okay i will change that since the NVR is on DHCP , but still finding it difficult to change the cameras IP address even after trying to use the config tool,
 
okay i will change that since the NVR is on DHCP , but still finding it difficult to change the cameras IP address even after trying to use the config tool,
Can you apply a hard reset to the cameras?
 
okay i will change that since the NVR is on DHCP , but still finding it difficult to change the cameras IP address even after trying to use the config tool,
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Yes, that IP range is indicative of the NVR's private server when using POE; it's a different subnet from the NVR's LAN.
You should have the cams and the NVR's LAN on a 192.X.X.X subnet if using an external POE switch .
okay thank you Tony