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teejay711
19-08-2013, 09:12 PM
Mitsubishi IND slim

Split system with 2 indoor cassettes.

Put my probes across S1 and the earth next to it from the 230v supply.
I was under the understanding that S1 was 208v-240v so was stunned when it went bang.

It blew a 6.5v fuse in the condenser board, replaced the fuse but now got e6 error and only 12v between S2 and S3

My question is, should it have blown between S1 and earth?:mad:

Tony

frank
19-08-2013, 09:47 PM
Mitsubishi IND slim

Split system with 2 indoor cassettes.

Put my probes across S1 and the earth next to it from the 230v supply.
I was under the understanding that S1 was 208v-240v so was stunned when it went bang.

It blew a 6.5v fuse in the condenser board, replaced the fuse but now got e6 error and only 12v between S2 and S3

My question is, should it have blown between S1 and earth?:mad:

Tony
This tells me that you either have a dodgy meter or it was not on the correct setting

install monkey
19-08-2013, 09:57 PM
was ur probe on the screw or on the end where the wire goes in, maybe arced s1 to casing
e6 is comms error- check the size of the fuse that went bang- if it was over 6 amp u fried the board, disconnect the s1 s2 s3 on the outdoor unit ,power up outdoor and test the terminals carefully
- as frank said if u had a crap meter and had the probes in the wrong holes- i ve had it with them lil **** meters at climate ctr-everytime i test a ballast on a light fitting-handy as pins are tiny-pop- new ballast
get ur boss to buy u fused test leads with 3mm visible contact area- health and safety requirement for live testing, and maybe some more company underpants!:o

teejay711
19-08-2013, 09:59 PM
This is possible
I have a cheap multi meter that I use just to take temperatures but today forgot me fluke which will gave a AC or dc reading. The setting was at AC.
Can I ask, if usually taking a reading across S1 to earth is this OK as it totally stunned me.

I expected a reading of 240v
TJ

teejay711
19-08-2013, 10:03 PM
yep it blew the 6.5 fuse in the board.
The system was ok so guess im paying for a new board then.

Tj

install monkey
19-08-2013, 10:05 PM
with a fluke t5 or t1000 its fine - as it wont trip an rcd circuit- other brands can cause trips- found this at me peril when working on petrol station fridges- pop-all the tills,pumps,lottery machine, silence!!! haha

teejay711
20-08-2013, 08:10 PM
ALL,

The fault was the PCB, I changed it today, hey presto......
So what went wrong so nobody else does what I did. 218 later.....

I originally tested S2 to S3 on A/C, with a multimeter, I later under stand this to be 24v DC, so at this point I think I broke the multimeter although it still gave me a reading.

Next I went straight to S1 to earth terminal, normally this would be OK but I think at this point I had broke the tester....... BANG.

Go get a new board at 218

Massive thanks to those who replied.

TJ

install monkey
20-08-2013, 08:14 PM
http://www.fluke.com/fluke/uken/Electrical-Test-Tools/Electrical-Testers/Fluke--T5.htm?PID=55986
you still need a new meter!:o

hookster
20-08-2013, 08:21 PM
Even a crap meter should not short on 24v!! The shunt resistor should easily handle your test.

install monkey
20-08-2013, 08:26 PM
maybe user error! or shaky hand syndrome!:o

Even a crap meter should not short on 24v!! The shunt resistor should easily handle your test.