Mitsubishi FX3U analog inputs

Electric3906 · Nov 19, 2018

Hi Team

I am having trouble finding the address of analog inputs on my FX3U-24MR PLC in GX Developer.

The MELSEC FX Series Programming Manual is very vague and seems to assume that the reader already knows the addresses of analog in's and out's.
The PLC has AD0 to AD5 printed next to the analog in terminals.
But GX Developer will not accept these as addresses.
I am downloading GX Works to see if that is clearer.

Any ideas?

nehpets · Nov 19, 2018

Welcome to the forum,
As far as I know,there aren't any integral Analogue inputs on the FX3U range, you need additional hardware for those.
It's the FX3g's that have integral Analogues.

Steve

Electric3906 · Nov 20, 2018

The FX3U seems to have analogs.
The drawing calls terminals AD0 to AD5 analog inputs and DA1, DA2 analog outputs.
The many vendors that sell the PLC all say analog ins and outs.

Mad_Poet · Nov 20, 2018

Near as I can tell, whether or not an FX3U has analog I/O depends on the precise
model number - and /or which modules are part of it. These three models are said
to have analog I/O points.

FX3U-4AD-ADP
FX3U-4DA-ADP
FX3U-3A-ADP

I suspect one will have to find the manual for the sub-module in question.
Good Luck.
Poet.

tragically1969 · Nov 20, 2018

Mad_Poet said:
Near as I can tell, whether or not an FX3U has analog I/O depends on the precise
model number - and /or which modules are part of it. These three models are said
to have analog I/O points.

FX3U-4AD-ADP
FX3U-4DA-ADP
FX3U-3A-ADP

I suspect one will have to find the manual for the sub-module in question.
Good Luck.
Poet.

They are extension modules, not PLC's

goghie · Nov 21, 2018

FX3U-24MR Does not have built in analogues. You can add extension modules on right side of PLC, or one extension board on front of PLC.

Electric3906 · Nov 23, 2018

Hi Team
An update: I have one analog input reading a 0 to 10V input.
My aim is to complete a chart that starts like:
-[RD3A K0 K1 D1]- equals Analog input terminal AD1.
This gives a monitored value of 0 to 4000 (ish) units. I can track the units changing value with the input voltage moving up and down.

The FX3U-24MR most certainly has one analog input so far.
But the other 5 analogs stubbornly refuse to play nicely. Maybe they are configured for 0-20mA?
I am investigating scaling on analogs. Will update when I learn more.

Cheers

Wasan · Nov 23, 2018

Please show us your device setting or Analog Input card that attached with PLC. We need more information.

Electric3906 · Nov 24, 2018

No cards or extensions. The PLC is all in one.

nehpets · Nov 24, 2018

It would appear that this is not an FX3u PLC per se, but a FX3u control board (skeleton PLC)(FK3U-24MR)
https://www.ebay.co.uk/p/Fx3u-24mr-...-Calendar/25020048329?iid=311983641058&chn=ps

I have not been able to find any documentation on this, but the RD3A instruction requires the special block number of the analogue input and the channel number to read this is then stored in a 16 bit 'D' register giving a reading of 0 to 4000'ish, I would appear the analogue inputs are grouped as three current inputs and three voltage inputs (don't know which is which) so the RD3A should be something like [RD3A K0 K0 D0] for channel #0,[RD3A K0 K1 D1]for channel #2,[RD3A K0 K2 D2] for channel #2 etc.

I did manage to find this https://www.lollette.com/support/pdf/PLC/FK3u-analog-485.pdf

Steve

lfe · Nov 24, 2018

Big confusion that you introduce in the title of the thread

Yo are naming as Mitsubishi a piece of hardware that's not of such brand

A real Mitsubishi FX3U looks like this:

Ronnie Sullivan · Nov 24, 2018

Fk not fx
And I'm not swearing there

Electric3906 · Nov 24, 2018

Hi nehpets

You have nailed it! Many thanks.
I have been trying all sorts of K and D combinations, but your information was spot on.
And, Ronnie Sullivan, the PLC is a FK not an FX.
I was working under the (incorrect ) assumption that the PLC was an exact clone of a FX3U. WRONG!
Yes Ife, I am easily confused and it looks that this is contagious. Apologies.
You guys are good.
Stay tuned for the next thing that stumps me.

nehpets · Nov 25, 2018

Glad to be of help,

Steve

Mitsubishi FX3U analog inputs

Electric3906

Member

nehpets

Member

Electric3906

Member

Mad_Poet

Member

tragically1969

Member

goghie

Lifetime Supporting Member

Electric3906

Member

Wasan

Member

Electric3906

Member

nehpets

Member

lfe

Lifetime Supporting Member

Ronnie Sullivan

Member

Electric3906

Member

nehpets

Member

Similar Topics