Siemens PLC Controller completed

[easttn]

Its an eye test. Seriously, if you ned it I'll post as a PDF. Gresh, how are you doing my RC friend.
Chaz

 

[Icefire]

Nice.

I have setup a 5$ 0.2*C accuracy probe (lm35 chip) which give 10mV/*C

Problem is my PLC is 0-10V with 10mV accuraccy. Any way to have my probe output multiplied by 10? That would give me 0.1*C resolution on my PLC.

 

[BeanAnimal]

You need an instrumentation amp... (OP-AMP) circuit or a purpose built amp. eBay is the place to look for probe amps unless you want to DIY.

 

[Icefire]

Yeah that's what I tought, I wanted it dead sample plug in, my probe have 3 wire. +5 - +30V, ground, output.

I'll make an opamp circuit

 

[Icefire]

With an LM324 op amp it's worst

 

[BeanAnimal]

?

 

[Icefire]

With a non-inverting gain of 10, I get 2.546 volts but the PLC's value fluctuate +-0.2V.

 

[Icefire]

http://www.allaboutcircuits.com/vol_3/chpt_8/7.html/conversion

I'll try a 4-20ma transmitter. basicly using a 25 ohms resistor to set a 0.1V (10*C) to 0.5V (50*C) converted to 4-20ma.

I can set the range I want with the resistor

 

[easttn]

Icefire,

Are you using Thermocouples or RTD, if RTD how many wires?
Nice link thanks.

 

[BeanAnimal]

Yeah the op-amp circuit needs to be fairly precisse due to the impedence problems. You can use an LM-324 but the supporting circuitry has to be a bit more complex. Burr-brown makes some very nice instrumentation amps that are much better suited to the application.

There is also a good app-note on the national site regarding PH amp design. I will see if I can dig it up.

 

[GreshamH]

<a href=showthread.php?s=&postid=9134852#post9134852 target=_blank>Originally posted</a> by easttn
Its an eye test. Seriously, if you ned it I'll post as a PDF. Gresh, how are you doing my RC friend.
Chaz

Couldn't be better. Like you I changed jobs, and we're in similiar fields now. I left my job being Beaver Patrol, to that of Bikini Inspector. Maybe we'll see each other on the job some day :lol:

Serioulsy, I'm OK and still at Reed

I need to talk to you about this, I'm ready to get this project finished and move on to another

 

[Icefire]

Bean I was using LM324.

 

[best49erfan]

Gesh,
for your actuators, or the motor driven or pneumatic?

 

[GreshamH]

eeks, how'd I miss this? electric motor linear actuators.

http://www.firgelliauto.com/default.php?cPath=86

I just redisgned it though after a great post from some one here on RC. I went to one of these:

http://www.firgelliauto.com/default.php?cPath=104

 

[GreshamH]

FWIW once again I am trying to get this one up and rolling. I hope Charles is stilla round as I need a bit of help. Chris should be hearing from me soon as well.

 

[BeanAnimal]

Great actuators. I designed a lift system for my light rack around one. The actuator will move a force multiplied pulley system. 1 inch of travel on the actuator will give me 5 inches of travel on the rack.

I have yet to complete the project because I am rethinking the lighting configuration and may incorporate a light mover to the rack.

The silly idea is to have the sun acatually rise and set... stupid but fun I guess.

 

[easttn]

I'm here brothers

I'm here brothers

Try to assemble the System we agreed to. It was developed to the parameters we agreed to. I see meddling before initial connectivity, newb mistake men! Stay the course!

Changes are fine, but I won't get in a quagmire of initial requirements to new needs- THEY ALWAYS TEND TO CONFUSE THE PLAYERS.

Gresham and Chris, you both have the same S/W baseline, the same Revision, same Touch screens & app, and the same OP-Code - both in S/W and H/w. You are both at where I am - if you don't see this as truth - plz post message here.

All future changes will occur within this thread to assist others.

If you guys do not have what you need (Ex. TP070 S/w clue me in. It is buried in MicroWin 4,0.)

Initial apps, pinouts and controls are developed......lets have a forum boys.

C'mon you wankers, free will-----------

Chaz-man

 

[H20ENG]

No worries Charles. Dont get scared, LOL. I always have the original copy backed up if I do too much damage
I'll post a new thread once I get my panel going so not to step on this one. CMon Gresh, who's going to win this slow race?

 

[lisaFL]

bump

 

[ron69]

Any updates on this?
I am very intersted in this! I am an electrical engineering student and will be studying plc's next semester. I'm going to start searching for the equipment right now. This would be great for my tank, and might help me get a jump on my next classes.

Any pointers on the best place to find good used parts? For now I gues im off to ebay.

Thanks,
Ron