Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[Champdriver]

Hi All


First time trying to set up a p 94 and am trying to bench test it
When connecting power to the p94 the sbec shows 5 volts and runs the reciever and steering servo fine. However on the dual motor side I am getting no power. When plugging in a multi meter one motor power distribution shows 26 ohm’s and the other motor power distribution will show nothing or occasionally 0.25 volts. I have tried using 6v source power initially and have also used 12 v source power with no difference.
Any thoughts or idea’s as to how to solve this would be appreciated.


Michael

[C-3PO]

Hi Michael,


What radio transmitter/receiver are you using?


Do you get any relay clicking when you power on?


Do you have your TX stick in neutral mid point at startup?


P94 datasheet


https://www.componentshop.co.uk/media/sparsh/product_attachment/P94%20Manual%20SMT.pdf


Regards

[Champdriver]

Hi c3po


The radio is an Frsky tandem XE with a TD 6 reciever and I have tried the throttle in several positions and no there is no relay clicking. In the  early P 94 instructions they mention the clicking but in the new version instructions there is no mention of the clicking, not sure if it was just forgotten or the set up was changed. With the automatic voltage meter getting the different readings on the power side I’m thinking it is dead.
The only other thing I can think of is from my floatplane flying days when I couldn’t get the beaver to start and I called up the chief mechanic and he told me to kick the engine firewall twice as hard as I could above and behind the rudder pedals and try the starter again, it worked. Apparently there were to big relays there that were a little bit sticky and just needed a little help it got me home anyways.


Michael

[C-3PO]

Hi Michael,


I just Googled your radio transmitter - a sophisticated piece of kit.


I wonder if the PWM/PPM frame rate is set at a higher frequency than the P94 can decode?


Normal standard would be 22 or 22.5 ms for a PWM frame length - I think your radio can perform much faster than that and may need a setting to be reconfigured.


Read that this radio RX (TD6) capable  of low latency 4ms output - the P94 will definitely not decode that!!! likely a config setting could be amended to get to 20ms


Do you have an older/less capable, basic TX/RX you could use (borrow) to test your P94?


Regards

[Champdriver]

Hi c3po
yes just got that new tx last week its very nice piece of kit.
Not sure if what you said is the problem as the reciever side of the p 94 seems to work ie. when i plug the rudder servo into the p 94 it operates normally with the tandem xe tx and rx. I do have a spectrum rugged dx 5 with reciever I will try but the issue seems to be on the motor output side as it shows no volts or just jumps around from ohms to volts on the smart multi meter (multi meter hunting). I am wondering if it may be the bench top power source I am using a DC variable out put power supply 30v 10amp and am wondering if the amperage is not high enough to run the P 94 (20amps) I also don't here the relays clicking (closing) however the clicking is only mentioned in the early P94 instructions and not the latest instructions. This is a sealed unit so I don't really have to many more options to try. It's probably cheaper to buy anew unit than to try and ship it to the UK for servicing and then having it shipped back to Canada in several months.


Cheers, Michael

[Shipmate60]

Be careful with the Dx5, I had problems with it on this mixer. Dave and myself did some testing and found that the pulse width of the Dx5 was incompatable with the mixer. I dont know if Dave developed it further but I doubt it as there wasnt many Dx5's in use.

Bob

[JimG]

Hi c3po
yes just got that new tx last week its very nice piece of kit.
Not sure if what you said is the problem as the reciever side of the p 94 seems to work ie. when i plug the rudder servo into the p 94 it operates normally with the tandem xe tx and rx. I do have a spectrum rugged dx 5 with reciever I will try but the issue seems to be on the motor output side as it shows no volts or just jumps around from ohms to volts on the smart multi meter (multi meter hunting). I am wondering if it may be the bench top power source I am using a DC variable out put power supply 30v 10amp and am wondering if the amperage is not high enough to run the P 94 (20amps) I also don't here the relays clicking (closing) however the clicking is only mentioned in the early P94 instructions and not the latest instructions. This is a sealed unit so I don't really have to many more options to try. It's probably cheaper to buy anew unit than to try and ship it to the UK for servicing and then having it shipped back to Canada in several months.


Cheers, Michael

The output of the power supply will not affect the working aqs long as the voltage is within the limits. The P94 may be capable of transferring 20A to the motors but the relays will only require a small current to work, probably in the region of milliamps.
Jim

[Colin Bishop]

Have you emailed Component Shop about this? They are best placed to suggest what the problem might be. Is there a chance you could have connected up the supply the wrong way round initially which could have affected internal components.

Colin

[Champdriver]

Hi All


Thank you for your inputs but the problem is solved.


I just got off the phone with the component shop and apparently they had a few units sold last year with bad chips and mine was one of them!
When I spoke with Kyje and explained things he had concluded that I had in fact actually done everything correctly which made me feel good as " I know enough about electricity to be dangerous".


Anyways they told me to ship it back to the UK and they will fix it free of charge, this is extremely nice to see in today's day and age as there are still shops / vendors out there that provide what I call proper "customer service"[size=78%].[/size]


So at this point I would like to say thank you to the component shop.


Cheers,  Michael