Static discharge prevention

[bluenun20]

I have just bought a CCTV DVR and it came with a 1 meter length of wire with difficult to understand instructions.

I can see where I need to attach it on the DVR but where should the other end be fixed to?

I have my wooden floorboards exposed, should I fix it to them?

 

[josh1e]

I have just bought a CCTV DVR and it came with a 1 meter length of wire

what is on the end of the wire? a mains plug? a cctv bnc connector?

why would you connect a wire to a floorboard? do you find things usually work like that? must be cheap on the electric bill

I have a cctv dvr. 1 3pin mains plug, several bnc camera inputs & and audio inputs (3.5mm headphone jacks)

please take a photo or explain a little better

thanks

 

[bluenun20]

Like you I have 1 3 pin mains plug and 4 BNC connections for the cameras and an adapter. The system is working fine but in with manual came a 1 meter length of wire, on each end is a metal ring ( I don't know the correct term).

It is for prevention of static discharge. There is a tiny screw at the back of the DVR where the metal ring on 1 end of the wire is attached but it does not explain where the other end is supposed to be fixed to.

I will attach a picture of the back of the DVR.
It is the screw at the far right as you look at it that the wire is to be fixed to.

Not sure if the picture album has been added to my post?

 

[josh1e]

Hiya,

The instructions will guide you here, as it gets a little murky between manufacturers & models.

some DVR's are 12v dc. some are 240v ac.

you should not connect the earth of a 12vdc appliance to the mains earth, however if it is a mains voltage model, then it's fine to do that.

edit... the photo shows a 12vdc connection so you have an external transformer. I don't believe that you can earth this unit to a mains earth point. (can a sparky confirm? I thought bs7671 said it was not allowed?)

some CCV systems have the connections for an earth between the Cameras & DVR, although again this will be in the manual for the DVR / Cameras.

thanks

 

[tim west]

was there a wristband included? It may be for when you open it up to either service it or change HDD's?

 

[bluenun20]

Yes it is a 12VDC connection.

The length of wire and seperate instruction page was packaged with the remote control.

The main user manual that came with the system is easy to follow (in good English) but this seperate page is losing something in the translation.

I will copy one of the paragraphs just as it is written.

"Static discharge prevention

Static discharge would damage the device. If the static discharge prevention is not good enough, the device would be faulty completely or discontinuously.
When installing the device, connect the attached grounding wire in accordance with the following diagram. After that, the housing is connected to the ground and the static will discharge to the ground via the wire."

The diagram only shows where the wire attaches to the back of the DVR, not the other end.

No there was not a wrist band included with the kit.

 

[josh1e]

while i was looking through part p & BS7671 i read you cannot connect a 12vdc device earth to mains voltage earth.

(any sparks who can confirm / correct please comment here)

so i "assume" that the earth bond you have is for when you install the hard drive or possibly but unlikely for normal earthing.

nothing you are going to do with it is likely to cause an earth fault, for the average user these are quite resilient.

For further advice i would contact the company who sold it to you / the manufacturer. If the instructions don't supply clear instruction as to where to connect your earth, you could introduce problems by connecting it to the wrong place.

hth

 

[tim west]

sounds like it may be suggesting its connected to a ground plane of some sort for instance from a chassis ground in a rack for instance.
The power supply for the unit may be class 3 (check for markings on PS)allowing an operational ground or static discharge path but with no physical electrical path relationship between supply side and output side and the outer casing will be isolated even if connected to the mains supply earthing, in other words the casing will not become an earth fault loop path merely a path to ground for static buildup.

In saying that I wonder if the equipment is so sensitive whether some form of surge protection within this ground wire needs or has been incorporated to protect against surges such as lightning strikes?

 

[Europlex]

I have just bought a CCTV DVR and it came with a 1 meter length of wire with difficult to understand instructions.

I can see where I need to attach it on the DVR but where should the other end be fixed to?

I have my wooden floorboards exposed, should I fix it to them?

The obvious answer to this, as no one knows, is to go back to where you bought it from, and ask.

 

[Atilla]

Hiya,

The instructions will guide you here, as it gets a little murky between manufacturers & models.

some DVR's are 12v dc. some are 240v ac.

you should not connect the earth of a 12vdc appliance to the mains earth, however if it is a mains voltage model, then it's fine to do that.

edit... the photo shows a 12vdc connection so you have an external transformer. I don't believe that you can earth this unit to a mains earth point. (can a sparky confirm? I thought bs7671 said it was not allowed?)

some CCV systems have the connections for an earth between the Cameras & DVR, although again this will be in the manual for the DVR / Cameras.

thanks

Why not? Earth is Earth.
Not wise to connect the 0 line to earth. That said, you get earth loop problems then yes i would. (and get the sparks to sort the earth problem out)