Problem with a motor controler

 

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Craig colliass (Craig_colliass)
Member
Username: Craig_colliass

Post Number: 14
Registered: 3-2007
Posted on Thursday, June 19, 2008 - 8:33 pm:    Edit Post    Move Post (Moderator/Admin Only)

I have an interesting problem with the control for the spinner motor on the Saint
I have a perm motor switched via a 100 amp (300 amp max) contactor. This is operated by a 10A radio relay from yourselves connected to spectrum radio. All works well no problem.
The problem starts when I operate the wheel motors with the disc motor off, the 10A relay cuts in for a second and then drops out as if there is a stray signal going from the receiver to the relay the led gose on. If I run the motors slowly up to full power the fault dose not seem to occur so often, I have tried all connections and they are sound, and put the relay on different channels on the RX, also shielded the RX and the relay in an aluminium box with no change in the fault. The RX is powered via the BEC on the Sidewinder speed controller.
Any ideas as to the problem?
Many thanks

Craig
Admin (Admin)
Board Administrator
Username: Admin

Post Number: 814
Registered: 10-2004
Posted on Friday, June 20, 2008 - 3:28 pm:    Edit Post    Move Post (Moderator/Admin Only)

Craig,

There is a similar thread http://www.technobots.co.uk/discus/messages/7/2262.html?1213971951

I have put a response to your post there.
Bob Turner
Unregistered guest
Posted on Monday, August 25, 2008 - 7:57 pm:    Edit Post    Move Post (Moderator/Admin Only)

Hi,
I'm new to this but use a RC baitboat for putting bait out while carp fishing.
It's powered by two motors and is controlled by varying the power to each motor (a bit like driving a tank). Recenlty I lost most of the power to one motor, but only in reverse and this obvioulsy makes it difficult to operate.

By process of elimination I've established that both of the motors work and the two speed controllers are OK.
I think the fault is with the receiver, a Futaba FP-R115F (40mhz) as when the leads from the speed controllers are swopped about to the pins on the receiver the fault occurs on the "other" motor.
Q1: Am I on the right track?
Q2: What is a compatible relacement as I think this receiver has been superceded and I can't find an original one anywhere?
Q3: Could it be something to do with the crystals?
Any help or advice will be greatly appreciated.
Admin (Admin)
Board Administrator
Username: Admin

Post Number: 855
Registered: 10-2004
Posted on Tuesday, August 26, 2008 - 8:22 pm:    Edit Post    Move Post (Moderator/Admin Only)

Bob,

You did not say which speed controllers you have. The most common cause of loss in power in one direction is a failed reversing relay or failed MOSFET if a full 'H' bridge controller.

It will not be a crystal problem and unlikely to be a receiver problem. If you have a servo, try that in each of the receiver channels you are using to see if you can get full travel. Any single conversion 40MHz Futaba receiver will work, even our Cirrus receiver will do the job.

Whilst your tests indicate otherwise, my money is on the speed controller! Try the servo test first though.
Bob Turner
Unregistered guest
Posted on Wednesday, August 27, 2008 - 7:00 pm:    Edit Post    Move Post (Moderator/Admin Only)

Hi Paul,
Thanks for the reply. I too thought it was a faulty speed controller and have fitted a new one. They are Marine Max 3i Sonic.
I think the system is set up as follows. 2 speed controllers, each one has a 12V input and an output directly linked to each of the drive motors, i.e one speed controller controls one motor (there are no servos in the system) and each one has a small lead that is plugged into the receiver. When I select "reverse" the polarity of the output from the speed controllers is reversed with the voltage being dependant on how much I pull the appropriate lever on the handset. If I switch the connections to the receiver so that controls on the handset are effectively reversed and controlling the "other" motor then the motor that wasn't working works and the motor that was OK won't work in reverse. I think this means that the speed controllers are working OK but not getting the correct instruction from the receiver.
In any event I think it worth trying a new controller so I'd be grateful if you could suggest one for me and I will of course purchase it from you.
There is another function on the boat to drop the bait from a hopper that is RC controlled so I need a compatible receiver that has at least 3 outputs and it must be capable of being powered via one of these as there is no seperate battery in the boat.
Hope you can understand what I'm trying to say. If you wish to speak to me to clarify anything please ring me on ******** and I could also give you some credit card details and address for the receiver at the same time.
Regards
Bob Turner
Admin (Admin)
Board Administrator
Username: Admin

Post Number: 859
Registered: 10-2004
Posted on Wednesday, August 27, 2008 - 9:27 pm:    Edit Post    Move Post (Moderator/Admin Only)

Hi Bob,

Sorry but not heard of that controller before, do you have a web link to it?

I still think you should try the servo because I would still be surprised if it was the receiver. What model transmitter is it, are you sure the transmitter trims, offset or dual rate is not causing your problem.

We are always happy to sell you new products but that's not much use to you if it does not solve your problem. See if you can borrow a servo if you don't have one.

Regards

Paul
Bob Turner
Unregistered guest
Posted on Thursday, August 28, 2008 - 6:20 pm:    Edit Post    Move Post (Moderator/Admin Only)

Hi Paul,
The transmitter is a Skysport4 T4VF. The transmitter trims are OK but I don't know what an offset or dual rate is so don't know if it is causing my problem.
If you would let me know what receiver I need I'll just buy it from your website; would the Cirrus 4 Channel 40MHz FM Receiver - Part No: 3120-001 do?
Regards
Bob
Admin (Admin)
Board Administrator
Username: Admin

Post Number: 861
Registered: 10-2004
Posted on Thursday, August 28, 2008 - 7:26 pm:    Edit Post    Move Post (Moderator/Admin Only)

Hi Bob,

That transmitter does not have dual rates or offsets. The Cirrus is absolutely fine with Futaba sets and is our most popular receiver, obviously due to the low cost.

Regards

Paul
Bob Turner
Unregistered guest
Posted on Wednesday, September 3, 2008 - 5:59 pm:    Edit Post    Move Post (Moderator/Admin Only)

Hi Paul,
Just wanted to let you know that my baitboat problem has been resolved. I installed the new Cirrus receiver which I bought from you and everything works fine. There was definitely a fault on the Futaba receiver on channel 2.
Many thanks for your help it was greatly appreciated.
Regards
Bob Turner
Admin (Admin)
Board Administrator
Username: Admin

Post Number: 868
Registered: 10-2004
Posted on Wednesday, September 3, 2008 - 9:47 pm:    Edit Post    Move Post (Moderator/Admin Only)

Hi Bob,

I am very pleased to hear that solved it. Just goes to show we never stop learning, I would have put money on it not being the receiver.