help 4 a programming!

hi...
i'm doing a project which is wheelchair controlled by joystick n being controlled by PLC...so im using OMRON (CQM1H)PLC...the problem which arise are:
- in my programming, i put 1 motor as the output n it runs as 2 directions...so my hardware requires an external relay of 24VDC with 5 pins to change the polarity of the direction of the motor...but it won't work!...i used 2 external relay for 1 motor...is it the correct way to do?
-my program won't work at all as i modify it to many ways...please help me....
p/s: Tq..n sorry for grammar error...

Sounds fuzzy

Hi Suwek

Am I correct to deduce that you wanted your motor to run forward as well as backwards? so you connected a relay from the output to do the directional change, am I right?

One thing I'm not sure, can the motor run forward and reverse? If it could, what is the configuration to do that? Then maybe if that is figured out, you can try by using 1 relay or 2 relays depending on the situation, so when you position a forward, it will energize a relay to turn the motor forward; and vice versa.

Get where I'm heading?

regards
Sherine T.

You'll probably better off with a cheap DC Drive rather than a PLC. If you use a DC serial motor try to put your motor leads on the common side of the relay and the feed on the NO/NC side to change direction. You'll probably need a power on relay, a break resistor and some circuit for the protection/charge of battery (a diode, capacitor filter at least). If this is going to be OEM (you are going to mass produce) look into designing your own board.

Normally there would be two outputs required. One for a run/stop command (i.e. OFF = Stop, ON = Run), and one for the direction command (i.e. OFF = Forward, ON = Reverse). The type of motor and power supply (or drive) will determine how to wire it.



-Eric

I believe you should tell us what you want the wheelchair to do.
OK we get the drift it is to be electric propel.
What are the needs of the user?
Can they steer it themselves or do they need "power steering"
How fine do you want speed control?
How are you going to accelerate and decelerate and control it and what kind of rate?
What kind of slope?
How fast?

Now you are ready to decide if go
AC or DC. DC is probably better at least for the next several years.

Simple motor control or PLC.
If user is a para or quad then you may want to go PLC
If not I think simple motor control Curtis makes quite a few for this aplication GE may also be another make.

SUPPOSEDLY DC controllers can run away if there is a fault in the controller. CHECK to see if this can occur -- IF it can then a relay and E stop can eliminate this problem.

Dan Bentler
Seattle

thanks people!..
my project worked out & i've figured out that i've made wrongly connections for the relays...it comes like this...
-the NC should be connected to the supply while the NO connected to the ground..
-the (No.2) pin should be connected to the PLC (the address of the output)
-the (No.1) pin connected to the motor
-the (No.5)pin connected to any of the (-)....
so..it worked!