Bab ground

What kind of results are you looking far? Ground resistance? A multimeter will only confirm continuity.

If the service is is a center tap xfmr (240/120)... You can check voltage from A&B phase to neutral and A&B phase to ground, the potental (Voltage) should be the exact same. Or you can run a seperate wire from panel to service (where the xfmr is bonded) and check the OHM's should be a dead short.

my system is 480vac 3ph 60hz. if i get a ground tester what would by a good result and a bad result. what is the limit.

thanks

Assuming you are concerned with the saftey ground, and your xfmr is delta/wye voltage test is a very quick way to to see that the xfmr is bonded correctly. But to be sure you can still run a seperate wire from equipment to point of bonding to ensure the continuity of the "saftey" ground this should be no more than .5 ohms. If it is a long distance you need to subtract the resistance that you have on your test wire.

The mining industry requires these types of tests every year or if equipment is relocated which every comes first....

The simplest test to find out any equipemt connected to good ground or not is as followes

By a test lamp ( that is a bulb of 100 wates connected two 1 meter wires )

Now proceed as fallowes first test the supply voltage appeares at the input of the equipment by touching ( the phase & nutral of the input supply terminal) the two wires of the lamp at the input supply point, the bulb will glow if supply swatch is on, Then touch Or connect one wire to the body of the water purifier & the other wire at a time alternatelively to the two terminals , if the eqipment is connect to good earth then the bulb will glow.

HELLO BAB GROUND .

IT HAS BEEN MY EXPERIENCE THAT IN THE CONTROL PANEL OF ELECTRICAL DEVICES IT WOULD MOST LIKLY BE BETTER TO CALL A PROFFESIONAL IN, TO RUN A VERY EXSTINSIVE CHECK ON WHAT EVER THAT IS NOT RUNNING OR WORKING RIGHT.

AS WE ARE PROFFESIONALS IN THE WATER TANKS OR OIL INDUSTRY LOOK US UP ON THE WEB AT WWW.DORNTANKS.COM IF YOU ARE EVER A NEED FOR WATER STORAGE .

BEST REGAURDS.

JOHN OR STEVE DORN

You have told that you are having 3 Phase 480 Volts,60Hz Supplly.Are you having a neutral along with your Supply.

You are having Neutral with your system it is easy to confirm your Earthing.Take a Test lamp first check with Neutral and phase Lamp glows.Then Check with Earthing Point and Phase if Lamp glows it confirms Earthing.

You are having a Multimeter check Voltage between Phase and Neutral.Check Voltage between Earth and Phase.Both should be almost same.Now check Voltage between Neutral and Earth it should be less than 5 Volts.

In case you are not having Neutral in your system.The above said exersise shall be done with a good Earthing Point which you are confirmed.

I think above tests will give you the result.

Regards

KRAK