I am new here but with a big question

Hi everyone, I am Francesco from Italy.
I need to make a system that controls if thermocouples are working good.
I was thinking to take micrologix 1400 and 1762-IT4 for it but i need to configure the channels from the program because the clinet can test any kind of thermocouples. It is possible to make this, i read the manual of the card and say that the configuration workd is readable and writeble but don't say where to find this world on the program.
Thanks to all.

Francesco:

You have to use Adv. Config.
See attached figure.

this is good that you prepare plc configuration before start.
The client make a test with type J, when finish on the same channels put thermocouples of type K and start again. But the client don't have to enter in advanced config of PLC he have to make by HMI. If there is a way to change configuration of a channel by program.
Thanks for your answer widelto but maybe i was not so clear in explanation before. Hope that now i am more clear.

But the client don't have to enter in advanced config of PLC. He have to make by HMI.

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Sorry, but there is no known published method of re-configuring the 1762-IT4 from anywhere except the RSLogix Configuration menu.

I suggest that your client use two or more 1762-IT4 modules, one module configured for each type of thermocouple to be tested.

If your client insists tht he must have the ability to reconfigure a single Thermocouple module from within the program using his HMI, then tell him he must jump backwards in time and get a SLC 5/03, -5/4, or 5/05 with a 1746-NT4 module. For the old SLC 1746-NT4 thermocouple modules, you could reconfigure those from within the operationg ladder program.

Some old things are still better than the new replacements!

Thank you very much for your answer Lancie1. I have to change the controller and module then. Maybe with the compact logix? however the client don't want to spend much.
If i configure the channel for type J and select RAW data, can i connect also the K on the same channel and scale in different way in the program? can work in this way?

I think that trying to scale a K thermocouple to be read on a J-configured module would be difficult, error-prone, and mostly a waste of time. Thermocouples are not linear, so your scaling equations would be complex (if you could ever find the right parameters).

The cheapest way is probably to buy a second 1762-IT4 module. Why is that not acceptable? Once configured, you could have one module for J and one for K, with no setup from the HMI required.

The only reason I can think of is that maybe your client has a setup with only one set of 4 connectors for both J and K thermocouples. I would think that adding another set of connectors (and a 2nd IT4 module) would stil be cheaper and better than any other solution (if you already have the MicroLogix 1400 and one 1762-IT4 module). You can add up to 7 expansion modules to the MicroLogix 1400 PLC, so you should have plenty of room to add as many IT4 modules as you need for both J and K thermocouples. Configure one IT4 for J and one IT4 for K - what could be simpler and better?

The problem is that the client can test up to 12 thermocouples on the same test. This is why is not possible to have one for j and one for k. I don't have yet the micrologix nor the module so any other system can be acceptable if keep the price low.

yes you can use raw data.
make the calculations for each type of sensor and display them all.
Client makes a choice which one it is and now he can validate the sensor.
As resolution will be best as the signal is seen raw without any calculation.
you will have to account for the CJC yourself.
this way you dont have to change the settings (i saw (in manual) it is a register so it should be possible inside program)
And you have to make accuracy checks yourself, but as it is only a simple check it will be fine. use a block in water and a heated block for checking of sensors.

The problem is that the client can test up to 12 thermocouples on the same test. This is why is not possible to have one for j and one for k.

Click to expand...

But if you used 3 each x 4 channels, then you COULD do the job with six 1762-IT4 modules.

Or you can do it the hard difficult way.

Hi to all, the problem is that the client is a factory that make thermocouples and they can also need to try other types like R or S but also others so become impossible to use 3 for each type. For the difficult way seems to be the only possible if i not change all the system. I have another possibility can i configure the channels from a c# program that i can make? for shooter, i see also the manual, and they refer to a word of configuration, but they don't say witch is, if you find that can you tell me? thanks to all for your time.

If I were you, I would switch to an Allen Bradley SLC 5/04 with one or more 1746-NT4 or 1746-NI16 Thermocouple Input modules. Those are guaranteed to be configurable from within the program, and complete instructions for doing the configuration are included in the user manuals. You could find a used one like this SLC 5/04 with rack on Ebay.com, which includes one 1746-NT4 module, for $979 US (or less if you want to bid on it).

http://www.ebay.com/itm/AB-ALLEN-BR...Systems_PLCs&hash=item2330e9617f#ht_262wt_872

From page E-4 of the 1746-NT4 "Allen Bradley SLC 500 4-Channel Thermocouple/mV Input Module User Manual": (See attached picture)

Are you able to obtain a Spectrum Controls Universal Analog Input card? They are configurable in the ladder and can read just about any type of input, thermocouples included.

http://www.spectrumcontrols.com/ab-1762.htm

PArt number 1762SC-IF8U

i can not program a micrologix so sorry can not help you , however when reading the manual i see there are registers you can write to to change the setup.
most people do it with advanced configuration but it is possible to do it on the fly inside your program.

I would sell them a good calibrated meter for mV like a keithley or fluke or any kind.
When it has a analog output you can take this to the PLC to get a faster automated test.
They MUST have a calibrated meter to give any certificate, a PLC is not enough for this.

most people do it with advanced configuration but it is possible to do it on the fly inside your program.

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Yes, for the older 1746-NT4 module, but not for the newer Micrologix 1762-IT4 module. Perhaps the non-Allen Bradley Spectrum Controls brand Universal Analog Input card that FactoryTalk recommended will also allow configuration from within the program. Usually those Spectrum Controls modules are quite a bit more expensive than the Allen Bradley modules.

Lancie1 said:

Yes, for the older 1746-NT4 module, but not for the newer Micrologix 1762-IT4 module. Perhaps the non-Allen Bradley Spectrum Controls brand Universal Analog Input card that FactoryTalk recommended will also allow configuration from within the program. Usually those Spectrum Controls modules are quite a bit more expensive than the Allen Bradley modules.

Click to expand...

I've used the IF8U before and can confirm the individual channels are configured in the ladder. I usually just use a COP to move the settings into the card on the first scan, but I've also changed the configuration word manually on the fly via the data table editor with no issues. So there's no reason a more automatic setting change via the ladder wouldn't work.