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Re: Insulation testers
Take a look at a conventional loop tester. The Martindale is great for a ‘sanity’ check, but personally, I would use a conventional loop tester that circulates the appropriate test current. Again, get a good one. Robin or Megger or Alphatek are all good makes. Make sure whatever tester you end up getting has appropriate test prods (GS38 & all that good stuff) or has internal fusing for your protection & well being.
Re: Phillips Tv Manual
If you just need an instruction manual, go the the Philips web site ( http://www.consumer.philips.com/consume … e=CONSUMER) & down-load it. If you need a Service Manual, then SEME is probably your best bet. Note that Philips recently announced that paper (TV) service manuals will cease to be published & will only be available on CDs etc.
Hope this helps. 😆
Let me know if you need any further help.
Re: Smeg SUK61MFX oven has died
Lets start with the basics – have you checked the fuse or MCB in your Consumer Unit?
Is it a single or double oven? If it is a single oven, it may have a 13amp plug on it ( 😕 ) check the fuse.
Of course, if you are unsure or are not competent, get someone in to take a look.
Re: Insulation testers
Why not try a second hand item? Stewart of Reading is supposed to be quite good. Tak a look at http://www.stewart-of-reading.co.uk. They used to do lot of hand-crank meggers real cheap.
Personally, I use a Metrel (Aphatek) tester. Good device – but may be beyond what you wish to spend.
Re: Bosch HBN435AGB/01 Oven
Guys
Thanks very much. Too much chocolate today & not enough Brains 🙄 I guess I need to read the e-mail more carefully 😉
I just checked the CD & stock status – so, I’ll have it for Wednesday no probs.
Re: Bosch HBN435AGB/01 Oven
Dave
Thats what I need – the (Bosch) part number is not shown on the SEME CD, nor is the fan-motor
Thanks
Re: Bosch HBN435AGB/01 Oven
Do you know the SEME part no? I have an SEME account so it would be easier to get the part from them.
Thanks 😆
Re: Suk90mfx – not heating properly in Fan Mode
Graf
If you are unable to confirm insulation and earthing after repair, I would advise that you seek help from a proffessional.
Regards
Re: Cooker trips circuit breaker
Steve
You fail to mention whether the RCD (thingy with a test button trips) or the MCB (individual circuit breaker trips). I strongly recommend that you have a qualified individual look at the cooker. A qualified individual will be able to check the insulation of the cooker and the RCD trip levels as required.
Either way, you could have an insulation failure. In my view, NEVER disconnect the earth 😉
Regards
Re: Philips built in oven flashed and died
Eddie
Get someone in to take a look. Normally if a circuit breaker trips, this indicates a possible insulation failure.
Sometimes as result of the fault, the cooker control switch (on the wall) is also damaged.
😉
Regards
Re: Comet’s new service centre
Just to add to this thread – I noticed a large banner today outside the Comet Service Centre in Watford advertising for Domestic Appliance Engineers.
Re: SatNav
Been following this with interest. Been using Navman with a Compaq PDA. It certainly saves a lot of time and like most comments, about 99{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} accurate.
Saves struggling with a map etc.
Recommend it each time. It unclips from the windscreen mount so can easily be concealed in the car or taken with you.
Re: NICEIC
Dave
No problem. Thought I’d throw a curve in – looks like a similar situation to gas but with electrical work.
Re: Earth Loop Impedence Test Equipment
Simonb
Sometimes low insulation on a motor can be due to X & Y capacitors that are used as interference suppressors (I don’t know if they are fitted directly to the motor) – so I would also be inclined to check these.
An RCd will generally trip if the leakage current in the cpc conductor exceeds 30mA.
The 0.5Mohm is for the electrical installation. Keep in mind that you are testing with a dc source when using a megger. When ac is supplied to the system, the impedance (as opposed to resistance) can now be different.
The insulation values that we all live & breathe by are set by the IEE.
I took a look at the IEE Code of Practice for In-Service Inspection & Testing of Electrical Equipment. For all class 1 equipment below 3kW the min acceptable value is 1.0Mohm.
So, if you leave an appliance with low insualtion in a useable condition – what happens if it smokes or gives someone a shock? Who is responsible (back to the previous discussion)? Getting the customer to sign a disclaimer may not help as they are not technically qualified. Personally, I would be inclined to disable it in a manner that it can be re-used after repair & write it up on the invoice that it should not be used as it is dangerous.
Also keep in mind that a fuse (or MCB) is there for short circuit protection. For excess current protection, it takes a lot longer for it fail (becasuse more current is required). When a consumer unit fuse fails due to a short, it has to open in a specified period of time (normally 0.4 or 5 seconds depending on circuit type). The time to fail is governed by lots of different things. However, a key parameter is the Earth Fault Loop Impedance. If you take the supply volts & divide it by the earth fault loop impedance this will give you the Prospective Short Circuit Current for the circuit at the point of measurement. Now this is important, since it is this current at short circuit conditions that causes the fuse or MCB to open.
The RCD will open when there is difference of greater than 30mA between phase and neutral currents.
For a ring final circuit, max earth fault loop using a BS EN60898 type B 32A MCB is 1.5 ohms. If you have a radial circuit using a 16A MCB (BS EN 60898 type B) then max earth loop is 3.0ohms (ref. Amtech Ref Sheet 1).
If you consider a 13A (BS1362) fuse (like in a plug top) then max allowable earth fault loop is 2.53 ohms for 0.4 secs disconnection or 4.00 ohms for 5 seconds.
Your 17ohms is only true at 13-amps. You will need more than 13-amps to blow the fuse and only continual sustained 13-amps may make it fail due to overheating rather than a fault. I need to study some pretty horrible graphs (called I*2t characteristics) to define when it fails in excess of 13-amps 👿
As discussed above, disconnection time is the key to protection effectivity.
I hope I have not totally confused you with my ramblings 😈
Personally, if I come across appliance values less than 1 Meg, I want to track down what is the problem (I’m sure you would as well).
Unfortunetly, safety these days is turning into what is known as risk-management. Personally, I like to work to the various codes of practice so that I can err on the side of conservatism. You have to make a choice as to what standards you work to ( I’m sure they are very high). This is all very risk-management orientated.
Hope this helps. Look forward to hearing from you again.
