AVHC10 THC cannot read divided voltage

[shadowdog]

Hello and thank you

I have a Jasic Pro Cut 65
and homemade plasma table and an AVHC10 price THC
I have it all setup as per the price manual but I cannot get an arc voltage reading on the price LCD display when the plasma fires.
The price AVHC10 isolation unit is connected to a 50:1 output connector on the Plasma cutter.
I have checked and I am getting a 3.8v reading from the divided output port on the plasma but when I connect this to the price AVHC10 50:1 input I get no arc reading?
Anyone any idea when this might be or have any helpful checks I might do to find out where the problem is?
I did put 1 volt directly into the AVHC10 from a desktop supply and I did get a reading so I’m confused
Thanks in advance

[robertspark]

are the cables wired the right way around as the torch is negative (-) and the table clamp is (+) but as you are using the 50:1 divided voltage output of the driver.... check that the voltage polarity is correct with the Price AVC wiring

[acourtjester]

I agree with Robert check the polarity of the input to the Isolation Module. Your output of 3.8 volts with 50:1 equals 190 volts, the Price manual states up to 250 volts cutting voltage. How new is you Price unit the older ones had only a 2 connection for the voltage divider input to the Isolation Module, but the newer one have 3 connections. This is due to the addition of the Hypertherm 45 XP which may have a different voltage level (not sure).

[shadowdog]

Thank you robertspark and acourtjester yes, it’s the older price and the polarity was the first thing I tried. I send my cutter back under warrantee for a service and had them check the machine port and it came back with a clean bill of health. I purchased the price a while ago where it sat on the shelf until this lockdown gave me the time to get it setup due to lack of business. I don’t know if Albert is affected by the lockdown at price because he not very responsive to my support requests perhaps its out of warrantee now.

[robertspark]

can you take a photo of your wiring please at the price and the plasma

thanks

[shadowdog]

Checked arc ratio output, all is ok measuring at 3.1Vdc. Open circuit voltage is approx. 150Vdc so arc ratio measured is correct. Voltage output socket pin1 positive and pin2 negative and a machine output socket with start signal is pin1 & 2 of 4-pin socket and the arc ok is pin3 & 4.

The price reads nothing when the arc is fired

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It has to be the Price THC a fault here but all emails for help go down a black hole. Should have tested it when I purchased.

Thank again

[acourtjester]

Another thing you could try and that is connecting a small Battery to the input to the module to see if you get a reading, not sure if the arc ok signal will need to be there for it to display.
I had emailed Albert about 3 weeks ago and he replied then but did it again about 1.5 weeks ago and no reply at that time. Because of the distance no telling if there is a problem on his end, hope all is well with the things going around these days.
I tried to Google that unit (Jasic Pro Cut 65) to look at the manual no luck?

[robertspark]

I'm sorry, I know I'm probably asking the dumbest questions here, but you are the only one looking at it.

It looks like the wiring is correct.

Could you check (double / triple check) the wiring between the isolation module and the price AVHC, I presume that you've wired the black+white >> the black and white and the black >> black.

I'd suggest maybe just checking that the connections are copper to copper (as the manual shows a chocblock [connector block]... and its easy to grip the cable insulation and not the copper conductor.)

I presume you are in the UK, where are you (I'm near liverpool, hence I'd offer to help if you were close.... but I've never had anyone close when I've offered before).

Unfortunately the Price manual does not tell you what the voltage range of the white+black wire to ground is or I would have suggested testing it with a voltage in its range to see if the problem was at the isolation module or the PriceAVHC control box end..... maybe price can advise that and you can split the fault testing in half..... if it was a 0-5V voltage you could use a 1.5V battery for instance and it would give you a reading on the screen (in theory)

[shadowdog]

robertspark and acourtjester thank you again.
Yes, I will check the wiring again white to white haha. I’m located in Lancaster UK about an hour and fifteen or so from lovely Liverpool. I have a desktop power supply and ran 1v dc to the price a few weeks ago and I did get a reading, it read 160 which was way more than I would expect.

[acourtjester]

Well that is a start but I agree that reading is higher that should be. It may be you will need to have Albert get involved. this is from their web page. I also stated out of stock so they may have some sort of unforseen problem and this is the reason for the non-contact period.
2 year warranty

60 day money back guarantee (excluding return postage)

[robertspark]

You're about the closest anyone has been to me as they are normally down south... [I'm not far from wigan and southport.... but everyone knows where Liverpool is so its easier to start with that]

What with social distancing I probably can't be any help anyway.

at 1V and 50:1 it should not be 160V (obviously as you've pointed out). I was going to ask you to try the raw voltage input but I'm not sure where you've get a 100V or so DC power supply lying about.... you could try to hook it up to the machine (work clamp to (+) ...... the only problem is the (-) as you'd need to open the machine up and find a connection point by tracing the leads from the torch.

I would not suggest rectifying mains (if the thought does cross your mind) as you'll end up with ~340v as most power is still delivered at 240v despite the wiring regs and EU harmonisation attempt. If you have a 110 site transformer (or 115V shaving socket??) that could be rectified with either a 1/2 wave or full wave bridge rectifier of 1N4007 diodes to approx 155V..... but be careful as DC bites and does not let go.... but if you've got a benchtop power supply you probably know what you are doing.

The problem with using a machine is obviously you need to keep it cutting to get a reading.... I always found it hard to cut with one hand and look at the THC voltage reading.... hence a higher voltage stable power supply is always a better idea for testing.

I guess to test the isolation module you could feed it from the benchtop supply something like 2Volts into its 50:1 input and see what the voltage is being feed via the back+white wire to the price AVHC which may tell you which end is fried.

Seems to be the first Price AVHC that anyone has found a fault with (its normally the other wiring + ports and pins setup everyone has problems with with the motion controllers). Price are based in Dublin, and I'm not sure what lockdown has been like there and social distancing etc etc hence that may be what is putting a go slow on communication from them. (I've never dealt with them though and don't have their THC, but their manuals seem good and the feedback from users of their THC has always been good)

[robertspark]

I also stated out of stock so they may have some sort of unforseen problem and this is the reason for the non-contact period.

Because of COVID19 + any lockdown some companies are listing everything as out of stock and closing their storefronts so they don/t have to do shipping and can shut up shop (literally) .... maybe that will change (ive not had too much of a problem here just post / deliveries are taking a bit longer than normal to arrive)

[shadowdog]

robertspark and acourtjester thank you yes it could be lockdown that keeping him away from his email. I will try injecting 100v plus to see if i can get a reading but i want to use low voltage so I may just wait for a reply and check the date i purchased it tomorrow to make sure im covered.

In the meantime i will have to cut without a thc
thanks again