Power panel questions
 

I've have a power panel that is faulty. The glow output stays at 12v. Has anyone seen a simlar issue themselves and managed to fix it ? I don't have a schematic but I can solder, etc.

It is like the bottom one shown here :

Also, please will someone advise on the use of the glow current settings control and meter and how to make the most of it. Is this really better than a simple nicad glow clip ?

[link]http://www.sussex-model-centre.co.uk/shopexd.asp?id=1413[/link]

RE: Power panel questions
 

Are you measuring the glow output with or without a load? It's quite common for them to read way above 1.5 volts without a load. What lead you to check the voltage? Was it buring out plugs, or were you just curious? The only time I've measured the output on mine was when someone else said their voltage was high. The circuit used in most power panels doesn't actually lower the voltage, it pulses the power on an off. This will cause a voltmeter to read higher than 1.5 volts when there is no load.

I use power panels exclusively. I like being able to adjust the output so I get a consistant glow. I've tried the rechargable glow ignitors and personally don't like them. I hand start my plane engines and I get much more consistant starts by using a power panel. I'm sure there will be many who disagree with me citing things like the possibility of the wire getting caught in the prop or the convenience of being able to carry the ignitor to the flight line in case the engine dies on the runway. However, power panels have worked well for me for years. To keep the wire out of the prop, always set your flight box to the side of the plane and then run the wire under the wing and then over the top. This way when you remove the wire, you have to set it behind the wing and well away from the prop.

To adjust the output, set the knob to low and install a plug into the glow connector. Gradually turn up the output until the glow plug wire is orange. Do not set it so high that it's glowing very bright orange, or even worse, white. I've read that if you drive it too high you can damage the coating on the wire.

RE: Power panel questions
 

Piper_chuck,
Don't do that!!!!!!!!!!!!! :D :D :D You confused me (yes, I know that's not hard to do). You changed your avatar on me!!! I almost didn't recognize your post without seeing those white legs in the kilt!!!!! :D:D:D

Ken

RE: Power panel questions
 

Surprise!!! Had to show some local team spirit. ;) It's been like that for a few days, you're the first one to comment, that I know of.

RE: Power panel questions
 

I have a Hobbico Deluxe power panel, on a crappy flight box I bought at a swap meet for $12 and the voltage reg doesnt work on mine either it stays at 12 volts and fried 1 cox .049 glow head and 1 nelson glow plug before I (duh!) figured it out, the fuel pump didnt work either:eek:..Rog
Oh the way I fixed it was to buy a new power panel for my crappy plastic field box...

RE: Power panel questions
 

Most modern panels put out a pulsed DC voltage at the full battery output. They vary the heating level by varying the pulse width (duty cycle). This is hard to see on a regular DC voltmeter. I'm not trying to say your system is not broken, just that it in not that easy to measure. An oscilloscope is a good tool for this while connected across a load (plug).

RE: Power panel questions
 

Power panels typically put out a pulse of 12 volts for 1 millisecond then nothing for 9 to 10 milliseconds then repeats. This averages out to about 1.2 volts. If you use an oscilloscope you can see this pulse train. You must have a load on the unit to have it work. The pulse is usually generated by an LM555 set up as a pulse generator with its output driving either a power transistor or Power FET.

RE: Power panel questions
 

Yes, this board also has a 555 (which I expect is running in ASTABLE mode :D ) but I'm getting zero volts on the supply pin on the device and there's nothing at all on any of the other pins. Two large (power) tracks had blown and I've bridged them but TBH, something else has more than likely gone and I can't be bothered to start drawing out the schematic from the components and the tracks. A new one is about £15 and despite what PC said about the glow clip, I'm not keen to pull the plug out more than I need to in order to set up the dial. I've also got two nicad glow clips and the pump has it's own switch anyway. Perhaps I will ditch the panel and build a circuit that auto-fills the tank to the correct level and then makes sure that it's empty when it's time to leave the field !