I have a FX3U48M Delema

I really did not think it was the PLC.
When the output comes on but the relay does not activate . . .
Did you check for continuity between the Y7 output terminal and the relay coil?

Does the common terminal for the Y7 read continuity to the 0 volts for the relay coil?

True story. I had a machine that was being problematic. I went through
every wire terminal in the panel, tightening them all up - and there were a lot
of them that were loose. When I was finished the machine ran with no more problems.

Poet.

Yup it was so simple I overlooked it Someone had got two wires switched around using the OHM meter Helped out locating the wires that were hooked up in the wrong spots. Thanks for your guys help I did learn more then what I did a week ago.


Now on to the next problem on that line lol if I run into more problems with the other two transfers that stopped working a month ago may I come back for more help????

Greg7683 > may I come back for more help????


But of course.
All too often it is something simple . . . or stupid.
And 90% of the time the problem has to do with a moving part.

Glad to hear you got it fixed.
Night all.
Poet.

Ok I'm back what is the controled power where does it come from and where does it go I know it is well on this system it seems to be the negative 24V but when I push the button nothing happens it just keeps saying no controled power on the hmi I used to get it working by jumping a wire in the start button but doesn't work that way anymore I replaced the switch and still nothing.

Dear Greg,
Sorry it took so long to get back . . . My last entry was the last day of my work week
followed by my week-end and then this week was a little busy . . . . After today I
am back into the week-end then I'm on vacation next week.

Control Power.
I'd have to start with where the main power comes in - anywhere from 120 VAC to
480 VAC. Look for fuses and transformers in those circuits. Then look for power
supplies powered from those circuits.

If it was my panel . . I'd start by looking for every fuse in the box. Pull the fuses, one
by one, check them with an ohmmeter and replace any bad ones. Then I'd power it
back up and look for anything that looks like a power supply - check for volts coming
out and volts going in.

If nothing wrong is found then I'd learn about that particular HMI and how it 'knows'
there is 'no controlled power' and work backwards (towards the power) from there.

From the first problem, I would be looking for something mis-wired . . . something that
should be referenced to zero volts but isn't . .

If you have two similar machines, one working but one not then checking volts in the
good one and checking for the same volts in the bad one - find the place where the
bad one is not what the good one shows and look for the problem from there.

(Having the schematics for the machine is invaluable.)
Poet.

Not having schematics is a really bad thing in order for us to have new schematics drawn up it has to be reengineered and that cost more then the company wants to spend lol. Yeah we did figure it out after a day and a half having to go between two machines checking the wiring between them. Thanks for everyone's help on these problems.

I realize this will be a lot of work . . .

But it is possible to draw your own schematics.
I use a program called Visio (was a visio product, now a microsloth product) to draw
schematics with. I think Open Office may have a suitable drawing program.

I would try drawing one little area at a time. Last problem was an HMI? Start with a
little box representing the HMI, with the cables and wires coming off it and lines
running to other boxes detailing where the wires go. Print the wire number (if it has
one) alongside the line.

Eventually one will have a collection of documented wiring which will enable rapid
troubleshooting. (One could also add 'normal operation' voltage levels to the print.)
Poet.

Yeah thanks we solved it a few misplaced wires.