Deric,

?

Even the fastest of fast blow fuses will not protect your mount in the event of a short. The purpose of the fuse is to protect the power supply and power lines. If current flows through these because of a short, the power supply and cables heat up very quickly and can start a fire. Before any fuse has blown, damage to electronic components is already done.

?

In regard to a nearby lightning strike, simply unplugging everything from the power is not enough. Electrostatic and electromagnetic forces from a nearby strike can induce significant current in any long lead whether plugged in or not. In anticipation of a nearby strike, long leads need to be disconnected from your mount as well. To this end, I have a single power cable coming to my mount pier, where the power divides into separately fused short cables to components on the mount. At the first sound of thunder, *one* power lead needs to be disconnected. I also have a single signalling cable (Ethernet) that comes to a network switch on the mount and is disconnected at the sounder of thunder.

?

To prepare for a direct lightning strike, keep your funeral insurance up to date. ?

?

-Greg

?

?

?

From: [email protected] <[email protected]> On Behalf Of Deric Caselli
Sent: Saturday, 28 December 2019 3:14 PM
To: [email protected]
Subject: [Losmandy_users_io] Mount power supply

?

What type of fuse or breaker should I use for short and over current protection? I have already been party to this before. My AVX mount went up in smoke after it shorted out and the Lithium battery did a rapid discharge through the mount. Celestron is replacing it, I dont want this to happen to the G11. Is their pre built devices or a good schematic for a device? I guess That I can build one but it has been awhile " a Heathkit Ham radio" Thank you and Clear skies.