Novamill just stopped working and im now stuck!

[Russellpalmer]

Hi all

basically ive had my novamill for around 9 months and never really used it, ive had a play, jog the axis and run a small program and that was it, but last week i switched on as normal and zero the axis all fine, but then the Pc came up with the machine not connected (rs232 and switch picture)

the drive board shows up 8 on the display so i assume this is correct?

ive tried 3 PC's on now and they all do the same,

ive tested all the cables and they seem fine,

the only software that will pick up the machine if the mint software, it says "machine found on COM1 but not running, download mint file now?"

click yes and it says download failed

any other program wont communicate with it and im stuck for ideas now

it has the latest v2.31 software and a 2.1 Eprom chip, can you guys help??

[Steve]

As the 7 segment display is lit we know the control card has power and is running.

The software and EPROM should be OK to run with the machine.

What control card is fitted to the machine? How old is the Machine?

Is the 7 segment display Red?

The most likely problem is the serial cable connection. Are you using the origional cable supplied with the machine? The one you should have is a Black Lindy cable BI01812GG which is used in conjunction with an internal BI01812A

Attached are links to both cables.

viewtopic.php?f=54&t=2352&hilit=rs232+cable

viewtopic.php?f=54&t=2351&hilit=BI01812GG

[Denford Admin]

And this post shows the cable you can make to go direct into the card (or use the info for testing):
viewtopic.php?t=544

If you run mintman, does "upload version" work and show the eprom info ?
If it does then I'd say the RS232 and cables is fine.

[Martin]

It may be worth trying MintMan first.

Run the file: MintMan which is located in the VR Milling installation directory (C:\Program Files\Denford\VRMilling)

Go to menu Setup -> Comm Port
Set the parameters to:
COM 1 (whichever machine is plugged into)
Baud: 19200
Parity: None
Data bits: 8
Stop bits: 2
Handshaking: none

Then press Download Mint & point it to the NovaMill.mnt file.
If you click on the Advanced Mode tab you should see the file being downloaded.

The only other sugestion is to check the internal RS232 lead. Some of the older machine were fitted with a 2 wire internal lead. There should be a diagram on here if you need one.

[Russellpalmer]

hi guys

went to do some more testing and now my stepper board seems to have failed, switched it on and one tiny led lit up on the 7 segment display, then thats it now when ever i power it up it wont light up, any ideas?

all fuses are ok

yours

Rus

[Steve]

The first thing to check is the 24V DC feed to the board.

These are on the connector next to the Z Motor.

See the attached link.

viewtopic.php?f=54&t=1627&hilit=motor+connection

[Denford Admin]

check the state of the 5V just to the left of the 24V input to the board
viewtopic.php?f=54&t=2126

[Russellpalmer]

ok will do when i get back from work, i take it the board has AC in to the left of the earth wire and 24V DC to the right?

The DC feed, i take it its just a +ive and -ive feed not 2 different positive feeds?

[Denford Admin]

If I remember correctly, you can put AC or DC on both/either so have a check on the drawings.
It's probably a rough 28V AC supply to the drives and 24V DC from a small (low current) PSU to the Logic

[Russellpalmer]

Hi all

i powered it up and the red 7 segment display lit up, well just the top part of the 8 eg " - "

tested the input power and had 28V AC on both sides of the earth wire

then i switched the machine off, switched back on and nothing again, (no leds lit up)

it seems if i leave it for 30 mins and switch it on then i will get the partial led light on but nothing else!

just my luck my easiturn blows a CD20 Drive, so i thought id have a play will my novamill then that stops lol

im not having much luck!

[Martin]

The Denstep board will trip out on overvoltage if the input voltage is too high. As Admin says the logic to the board should be 28V ac. If this rises slightly (29.5V) then the board stops working. The easiest way round this is to move the logic on to the 24V dc line. I think these are wire number 60 & 61.

[Russellpalmer]

Hi

quick question if im getting 28V AC feed to the logic supply (on the drawings it should be 24VDC) where do i source a 24V supply from?

cheers
Rus

[Russellpalmer]

just checked the next drawing and there should be a 24V dc supply above the spindle choke, when i finish work ill check it out

[Denford Admin]

The drawings in this forum show a 24VDC supply with 60 and 61 being the 24 output (as Martin correctly guessed)
Just be aware that this supply may be only capable of supplying a low current and may not be enough to also run the Baldor.

[Russellpalmer]

hi all

ive just checked my panel and there is no 24V dc supply, see below

am i best applying a 24V dc source direct to wires 28 and 29?





am i best applying a 24V dc source direct to wires 28 and 29?

[Denford Admin]

Yes, if you can find a 24V supply. It should be fused on the board, but you will need to check the new PSU has a fuse as well.

I think it's a much better idea to have 24vDC on the logic input

[Martin]

You should be Ok just removing the 2 wires from the control transformer (bottom left) wire numbers 27 & 28 I presume & moving them to the terminals 60 & 61 (24volts). Both wires should be long enough to be moved. I often rewire this on service visits.

[Russellpalmer]

hi guys

not been on for a while, ive still not got it sorted, is there anywhere i can get the denford board tested? i dont mind paying just as the setup was working then it just stoped?

yours

Rus

[Denford Admin]

we should be able to supply a service exchange - send an email to
service denford co uk
for pricing

[Martin]

Have just read through the thread.

It seems as though when you initially turn on the 7 seg display is on and it works then after a time it shuts down Is this the case?

The voltage regulator mounted on the heatsink at the right of the card has a thermal trip on it. I would open up the box and blow a fan on the unit and see if it runs OK then.

If so check the Unit is screwed down tight to the backplate. also check the stepperdrives and regulators are fastend down tightly to the heatsink.

Also check there is enough thermal compound under the chips.