field tester

[wittkopf]

Hi, anyone have any info on how to construct a field tester for electric(corded) power tools eg. grinders, circular saws, drills etc.? any help would be most appreciated.

 

[ericgibbs]

hi,
What Standard would you be testing too?
Is it for private or commercial use?

http://www.pat-testing.info/electrical-equipment-regulations.htm

 

[Nigel Goodwin]

You should also fill your location in, what's the point in people giving you advice that doesn't apply where you are (like the UK PAT link from Eric might not?).

 

[wittkopf]

I live in Alberta, Canada and have a chance to pick up a number of used tools for a very cheap price, by being able to test the fields I could determine if the tool was worth repairing or not ($$$).

 

[ericgibbs]

hi,
If you just want to power up the tools, to check that they run OK, depending upon on the power rating of the tools, you could use a battery pack and a mains invertor.

Upto about 250/500Watts, you could use a standard 12V 60A/H battery with a mains invertor.
It is possible to get mains invertors that are rated at 1KW to 2KW, but the types I have seen require a 24V battery.

It is possible to buy a 1KW to 2KW petrol driven mains rated alternator, they will fit on the back of a small truck.
This would be my personal choice as its got so many other uses.

Hope this helps.

 

[Nigel Goodwin]

I live in Alberta, Canada and have a chance to pick up a number of used tools for a very cheap price, by being able to test the fields I could determine if the tool was worth repairing or not ($$$).

As suggested, just plug them in and see if they work (obviously visually checking for damage first) - testers are generally for safety testing, NOT testing if things work.

 

[Hero999]

Portable appliance testing i often pointless in my opinion. Especially for double insulated appliances as there is no way of reliably checking for shorted turns in a motor, transformer or heating element. We were using a hair drier in a school science experiment and it melted down and nearly caught fire despite thet fact that it had only been tested a couple of days ago.

 

[Nigel Goodwin]

Portable appliance testing i often pointless in my opinion. Especially for double insulated appliances as there is no way of reliably checking for shorted turns in a motor, transformer or heating element. We were using a hair drier in a school science experiment and it melted down and nearly caught fire despite thet fact that it had only been tested a couple of days ago.

To be honest, it sounds more like the air intake was blocked or restricted?, but as it didn't 'catch fire' a few days earlier it probably wasn't at fault then?.

PAT testing is for electrical safety, not any test of it's operating safety, although the second part of the PAT test is to actually confirm that it works (first part is a visual inspection). Then for a class I appliance you measure earth bonding resistance and insulation from live/neutral to earth - these have to meet specific targets. For a class II appliance you measure insulation resistance from live/neutral, again it has to meet specific targets, at specific voltages.

What it's really all about is finding damaged electrical goods, cut's in mains leads, pieces broken out of casings, badly wired plugs, wrong size fuses etc. Almost all faults can be found by the visual inspection, and some items only actually receive the visual inspection.