? Inverters ?

[L8-Nite]

A question for electrical experts.

I purchased a 12V to 240V power inverter for travel use with an older mount I have. The inverter has a "three" prong receptacle to recieve a 240 volt plug, and "two" leads for connection to a 12 volt battery, however, there is no provision for "earth" ? Nothing is mentioned about earth / grounding in the safety literature that came with the inverter.

I have enough experience with electricity to know there is a real danger of shock without proper grounding., and 240 volts can be lethal.

Am I missing something here, with regard to safety with " Inverters " ? ? ? ? ?

Thanks for your replies.

[michael.h.f.wilkinson]

Grounding is regarded as not essential if your kit conforms to the double insulated standard, I thought. The symbol for that is:

[L8-Nite]

Grounding is regarded as not essential if your kit conforms to the double insulated standard, I thought. The symbol for that is:

Thanks Mike,

The symbol does not appear on our mount, it's an older TM mount for a Telemator. Except for plastic knobs, an all metal mount and scope.

Edit: Add photo.

[Pig]

Michael that is true but it is for human safety not especially for the protection of all the lovely transistors used within mounts, I am not sure about the earth but there should be some form of grounding built in.

[Adrian Condon]

Hi Mike,

I have an Inverter which does have the square within a square mark.

The documentation says that it is not for outdoor use.

It also says that the inverter can become very hot in constant use so be careful of the surface

it is placed on.

I use mine at star parties when there is no electrical connection to re-charge small batteries and

portal lights with the inverter inside my tent. (Also used to power the iPad).

I have thought of using it with a hair dryer outside to clear dew off the scope. But suspect that

the moist air could be dangerous. Would it work safely with RCD switch?

Cheers

Adrian

[L8-Nite]

Hello Adrian,

Thanks for bringing the risidual current device switch to my attention. I am not familiar with UK electrical systems, but this appears to be what I was looking for. I see there a variety of inline units are available, just need to do a little more research to choose the right one.

Thank you again !

Edit: By the way, overseas we call this device a "ground fault circuit" interupter. They are built into wall recepticles, however, I have not seen one which could be installed inline, such as the ones here in the UK.

Cheers.

[CraigT82]

I\m probably talking rubbish, but as I understand it...

The 'earth' in an electrical system is just the path of least resistance back to the power source... in your house's wiring that path is the ground itself, hence 'earth', and should fault conditions arise on your washing machine or whatever the current can flow back to the local substation through the ground until your circuit breakers trip.

On your mount the 'earth' will need to connect any metal parts of the mount/motors (which aren't live normally) to the power source (negative terminal on the battery) via the top pin on your plug, So if a fault occurs and the mount becomes live, the current will pass straight back to the battery until the fuse can blow. None of this matters if it's double insulated (is the top pin of the plug plastic or metal? And if metal is the pin connected to anything inside the plug?). I should imagine the top pin of the plug socket is electrically connected to the negative terminal when in use. I know that the 3 kilowatt inverters we use on our work vehicles have a separate earthing lug which connects to the vehicle body, and hence to the battery, but that's because the vehicle body offers a path of lower resistance than the negative wire.

Now I await the more educated and informed of the SGL community to quite rightly correct me!

Craig