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element testing

PostPosted: Sat Apr 12, 2014 7:01 pm
by whiskeyshiner
Wondering if any sparkies have heard of this my sparky mate tested my element using a mega and got 77 mega ohms between earth and neutral and earth and active he told me it should be infinate resistance to be safe and told me not to use it till he had a think about what it could be. He doesnt do alot of work with element but said sometimes they can have moisture inside the powder . Anyway its probably nothing but he said best to leave it till we sort it out

Re: element testing

PostPosted: Sat Apr 12, 2014 7:08 pm
by Yummyrum
TV tech cap on ....not sparky ...but I would not be too worried about that .At worst its a leakage current of 30uA ( 30 microamps)

Consider that earth leakage detectors (RCD) trip at around 1000 times that amount .

As long as you have an RCD on your switch board and your keg is earthed ,I don't see an issue

Re: element testing

PostPosted: Sat Apr 12, 2014 7:22 pm
by whiskeyshiner
Thanks yummy yeah he tested my rcd and it tripped so maybe where both being careful he does alot of industrial stuff so not alot of elements

Re: element testing

PostPosted: Sat Apr 12, 2014 8:47 pm
by punchy21
Heating elements are considered safe down to 10 000 ohms or 10k ohms, so your 77 Meg is absolutely fine... Thought he would have known that :think:

Re: element testing

PostPosted: Sat Apr 12, 2014 11:21 pm
by whiskeyshiner
punchy21 wrote:Heating elements are considered safe down to 10 000 ohms or 10k ohms, so your 77 Meg is absolutely fine... Thought he would have known that :think:


Yeah dunno mate he does comercial doesnt touch elements im no sparky but i would of thought it would be infinate to i mean if there a resistance does that mean a tiny tiny bit of current is getting through? Thanks for your expertise though im going to tell him your opinion ill give him a call tomoz because in the end hes my sparky and i have to go on his advice im definately not qualified to comment thanks punchy

Re: element testing

PostPosted: Sun Apr 13, 2014 7:28 am
by L'ambeq
Hello Whiskeyshiner,

two things seem to be important for me:

1. How much power does your heating element have?

2. What kind of meter did your mate use to measure the resistance?

1. Any electric device like motors, heatings aso are allowed to have an leak current against earth, depending on the power they have. This can be 3,5mA or for more powerful devices 1mA per kW up to 10mA for 10kW. (Elements with Protectionclass 1 connected to earth)

2. To measure the insulation resistance you have to use a meter with at least 500V of testing Voltage in DC! You should get a value of 0,5M Ohm minimum

Heating elements have an insulation inside the tube which is hygroscopic, so when the element is not used for some time it succs water, the insulating resistance decreases and the failure current increases.

If you have installed an RCD (which I can recommand anyway) it will cut off if the current is at the limit. Usually should be 30mA maximum

What can you do if this happens? You can ask your sparky- mate to connect the element to a lower voltage but without the PE (earth), let it heat for an hour or two and the insulation will dry very quick. After this procedure the resistance should be back to at least 0,5 M Ohm!

Do not touch the element or connectors during this time!

I hope this will not be confusing you, if you have questions plaese ask!



Expect the unexpected!

Re: element testing

PostPosted: Sun Apr 13, 2014 12:14 pm
by whiskeyshiner
Its a 3600w element i know he used 500v "mega" he called it because i remember asking why it was a 500v meter if it was only going to run at 240 thanks for the heplful response he said to run it without touching it to dry it out i just didnt want to post that in case someone thought it would be okay and got a boot thanks agsin for the helpful responses :handgestures-thumbupleft:

Re: element testing

PostPosted: Sun Apr 13, 2014 12:41 pm
by MacStill
3600w ? was it on a 15amp circuit when it tripped the RCD ?

Re: element testing

PostPosted: Sun Apr 13, 2014 2:41 pm
by punchy21
whiskeyshiner wrote:
punchy21 wrote:Heating elements are considered safe down to 10 000 ohms or 10k ohms, so your 77 Meg is absolutely fine... Thought he would have known that :think:


Yeah dunno mate he does comercial doesnt touch elements im no sparky but i would of thought it would be infinate to i mean if there a resistance does that mean a tiny tiny bit of current is getting through? Thanks for your expertise though im going to tell him your opinion ill give him a call tomoz because in the end hes my sparky and i have to go on his advice im definately not qualified to comment thanks punchy


Your element is safe to use mate - judging by your quoted insulation resistance of 77 M ohms. Your insulation resistance is very high... That's good :handgestures-thumbupleft:

Your earth resistance needs to be low - less than 0.5 ohm. This is the point between any metal surface on your keg and the earth pin on your plug top.

Sorry I wasn't trying to have a go at your sparky too :romance-kisscheek:

Re: element testing

PostPosted: Sun Apr 13, 2014 4:55 pm
by whiskeyshiner
MacStill wrote:3600w ? was it on a 15amp circuit when it tripped the RCD ?


Yeah sorry mate i should of said he tripped the rcd with his tester the element didnt trip it the circuit. Yeah the 3600 is on its own 15 amp circuit i use for my welder very impressed with how quickly it tested the water again today. Boiled for an hour mate retested this morning infinate resistance ( well my mate said it will read infinate once over 200meg ohms but its very safe at this level) :happy-partydance: i knew the elements were 100% fine just didnt wanna mess around with something i dont understand

punchy21 wrote: Sorry I wasn't trying to have a go at your sparky too :romance-kisscheek:


No worries mate i didnt think your were :handgestures-thumbupleft: i appreciate you input cheers

PostPosted: Sun Apr 13, 2014 8:45 pm
by Furynfear
Mate I'm a sparky and elements of any sort will never pull infinite on a mega. I deal with elements all the time. It's ok to use

From memory a normal appliance needs to be above 1megaohm but a heater will be. 0.1megAohms. The needle will barely move on a an anolog mega meter.

The problem with sparkies especially commercial ones is is that they only really run cables everyday.

Sent from my GT-I9505 using Tapatalk

Re: element testing

PostPosted: Sun Apr 13, 2014 9:25 pm
by Yummyrum
And while all this element leakage current is perfectly safe and causes no issues to the distiller.....Completely OT here.....many yers ago I was doing sound reproduction for a local theatre production .
15 minuates before intermission there was a loud buzz through the PA ....I copped the glares from the director....
WTF.......In those days I was young and keen... :laughing-rolling: Liked a chellenge .turns out the Hot water urn in the actors room was on the same curcuit as the mixing desk and the PA Amps back stage were on a different curcuit ...unfortunately the mixer and amps did not have balanced lines and the earth leakage current in the Urn caused the buzz :ugeek: when they boiled the urn for intermision

Re: element testing

PostPosted: Sun Apr 13, 2014 10:03 pm
by punchy21
Yummyrum wrote:I copped the glares from the director...


Let me guess - "You'll never work in this town again!" :laughing-rolling:

Re: element testing

PostPosted: Sun Apr 13, 2014 10:16 pm
by Yummyrum
punchy21 wrote:
Yummyrum wrote:I copped the glares from the director...


Let me guess - "You'll never work in this town again!" :laughing-rolling:
:laughing-rolling: You worked there too