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Are there any internal fuses in a CGE?

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#1 Snaproll

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Posted 17 August 2010 - 01:08 PM

At the star party someone mentioned that this might be worth checking, but before I open the mount I thought I'd ask if anyone knows for sure?

I also checked the power cord fuse which was OK, it didn't blow. It's a 3 amp which should be appropriate for the CGE, I think the max load is something like a couple of amps with both motors running.

If there is an internal fuse on the mount, I don't think it would have blown given that the power light is still on and there is power to the HC. I run the mount through a DC power cord via an AC to DC inverter. The inverter was off at the time of the lightning strike and appears ok, the 3 amp fuse in the power cord is ok, the mount just doesn't get past the "initializing" message on the HC.

The new HC is due on Thursday but I don't think it will heal the mount but it is worth a try before sending it in.

Any thoughts on the internal fuse thing though?

#2 gillmj24

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Posted 17 August 2010 - 01:18 PM

If it had a fuse worth a darn that would've prevented damage to the boards, then the mount would probably not power up at all. I could be wrong though i am not an electronics expert.

#3 rmollise

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Posted 17 August 2010 - 02:45 PM

If it had a fuse worth a darn that would've prevented damage to the boards, then the mount would probably not power up at all. I could be wrong though i am not an electronics expert.


Maybe si, maybe no. A fuse can protect electronics sometimes, but not always. The basic function of a fuse is to protect the _power source_. There is a fuse in the tip of the power cord, which is sufficient.

There is not a fuse in the world that will do pea-turkey to protect you from a lightning induced current from a close strike. It happens WAY too fast.

#4 Snaproll

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Posted 17 August 2010 - 03:58 PM

... to protect you from a lightning induced current from a close strike


That's what I believe happened. We lost our garage door motor as well, and some 1.5 amp, 12v battery chargers. The GFI part of the breaker may have tripped on that circuit. We lost our wireless router too, that was plugged into a UPS and probably on a surge protected outlet. That breaker didn't trip, but the breaker tripped on the observatory circuit did. The observatory is on a surge protected outlet and everything in the obs is on surge protected power strips. Normally I turn the breaker off on the obs and even unplug the mount and cameras, but that night I didn't because I was running a dehumidifier.

It was just weird the stuff that it did take out without frying anything else that's sensitive like the computers or TV. Nothing actually 'burned' so the strike was pretty fickle. I still don't know where it touched down, but it had to be >close< given the crack/boom was loud and no delay.

#5 Asimov

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Posted 17 August 2010 - 07:53 PM

What model CGE are we talking about? I have the pre pro mount - Absolutely no fuses in it.

#6 mclewis1

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Posted 17 August 2010 - 09:15 PM

There is no fuse in the CGE electronics.

There is a small diode across the raw voltage input that provides limited protection against reversing the polarity of the input voltage, and that input voltage goes through voltage regulators before it gets to the majority of the HC and MC logic. None of this will do much of anything to prevent damage from a lightning strike.

#7 Snaproll

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Posted 17 August 2010 - 10:13 PM

It's the regular CGE. I guess that answers the question, thanks.






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