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SKYDAT problem REF counter needed for testing

Posted: Sun Mar 05, 2006 12:41 pm
by gertcoetzee
My Skydat has been giving me problems since I got my Trike. From the start the fuel gauge was inaccurate, and eventually this was fixed when I sent the "black box" back for recalibration.

For the past two months I have a ref counter problem (as described before on this forum). Basically if I switch the one magneto off, the ref count (though not the audible refs) fall to zero, and at straight and level it registers only 3000rpm. See pic:
http://www.zu-dve.com/skydat.jpg

Skydat insists it is not their problem, and Niren suggested that I try to eliminate the problem by reading the refs independently with a ref counter. Does anyone in the Western Cape region have a loose ref counter & prepared to help me!?

Thanks!

Gert

Posted: Sun Mar 05, 2006 1:07 pm
by Morph
Not a spare one but next Saturday I am going to be doing my annual on AUK and I'll happily remove mine so you can test. I'll be at Morning Star all morning so if you fly in there we can kill two birds with one stone

Posted: Sun Mar 05, 2006 1:26 pm
by ICEMAN
Gert,


Ive recently had Skydat RPM problems myself.....

The system was initially wired directly to the motor and worked fine. Then i decided to install a regulator/rectifier/ and battery onto my plane.

The skydat (sx1) only has two wires for its power supply (and im told it reads the rpm via these wires)

I was advised that i had two wiring otions for the sx1 model:

1) power the unit directly off the battery (loose the RPM display, but has advantage of instruments working with an engine out)

2) split (distribute) the eletrical power wiring coming out of the motor ie power to the reg/rec and also a supply going to the skydat unit


i opted initially for option two, yet could not get even and equal distribution of power to instrument unit and also the reg/rec, This resulted in instrument inaccuracies(was only getting about 7-8volts to the instruments and about 12,8- 13 volts going to the reg/rec despite coming from the same source).


The power seemed to favour the path of least resistance (thicker shorter wires going to the reg/rec as opposed to longer thinner wires going to the instrument unit).... this might be your problem aswell.......

My co-pilot has a name and number of someone in jhb that can do a "conversion" for the skydats that allow it to power off the battery and has an additional "rpm probe" that wires to the motor directly..... PM me and i will give u his contact details if u want....... he quoted us the standard MPL price of R250 for the conversion... (ever noticed how MPL products and services seem to cost R250 or multiples thereof :lol: )


Hope this helps

Regards
Stan (now u have my name for your black book in your relentless quest to identify who we are)

Posted: Sun Mar 05, 2006 6:26 pm
by Duck Rogers
gertcoetzee wrote:.....eliminate the problem by reading the refs independently with a ref counter
Gert, I used an optical tach such as the radio control blokes use. Just hold it in front of your spinning prop and read the rpm. No need to do a seperate install.
I guess now you just need to find someone who has one in your area :?

Duck Rogers

Posted: Sun Mar 05, 2006 8:30 pm
by gertcoetzee
Yes, I suppose I could use an optical counter if all else fail but the idea for now is to read the signal coming from the enjin (the thin brown line) to see if it gives the same problem - if so, according to Niren it is something to do with the coils. (my ignorance shows heh!)