Gpsmap 60c Power Question - Proper Fuse

[+wiredcur]

My last post asked about proper voltage for a GPSmap 60C.

 

Now I'm wondering about the correct fuse to put in line. I ordered a hard wire kit for my motorcycle and it came with a 2 Amp fuse. However the diagram on page 77 of the owner's manual shows only a 1/2 Amp fuse.

 

Has anyone any idea if 1/2 Amp is big enough or if 2 Amps is too big?

 

Thanks again

[+WeatherMaker]

1/2 amp is plenty. I seem to recall actually using a 1/4 amp on my old Garmin 12. Out of curiosity, I'm running a current test right now (er, "currently" ). The GPSr is inside actively searching for satellites, on a 12 volt power supply. The current draw jumps around a little bit. No backlight pulls about 25 milliAmps, mid-level backlight about 55 mA, and full backlight about 72 mA. Shutting the receiver portion off (as in putting it in Demo mode), drops the current by 10 mA.

 

External amplified antennas draw power from the GPSr, but only 5 - 25 mA, depending on the model (at least the ones I've seen).

 

When in the power on/enter button diagnostic screen, a long beep pushed it to 100 mA, but in regular operation, the beeps are so short as to only bump it up about 7 mA for a split second.

 

Regarding your early voltage post, the same diag screen shows the internal voltage (when powered off a 12 volt supply) to be around 3.15 volts (2.4 V when on internal batteries), showing how the unit uses its internal voltage regulator. While the unit can take up to 36 volts input, it's less stress on the regulator (& less heat generated) to use an input voltage only as high as you have to, i.e. 6 or 12 volts (or even 14-16 directly from a solar module).

 

So, 1/2 is still larger than necessary. Use a 1/4 amp if you can find one.

 

Hope this helps.

Edited August 17, 2004 by WxMaker

[+wiredcur]

Just to make sure I'm getting the conversion right. The max draw you've ever seen was 100 milliAmps or 0.1 Amps?

 

So then would a 2 Amp fuse allow a dangerous amount of power through?

[+GOT GPS?]

I found a 1.5 amp 250 Volt Fuse in my Genuine Garmin Cable.

 

FUSE: AGC/3AG - 1.5 Amp

 

I remember one time having to replace this fuse, I think because of power problems from the cigarette lighter socket.

[+WeatherMaker]

Just to make sure I'm getting the conversion right.  The max draw you've ever seen was 100 milliAmps or 0.1 Amps?

 

Er, same thing, isn't it? Yes, 100 mA (0.1 amps) is the highest I saw.

[+Rubberhead]

Fuses are there more to protect your electrical system from a short in your device than to protect your device from a problem with your electrical system.

 

That being said, a 12 VDC car can handle 2 amps with no problem. If you have a short in your 60CS it will blow a 2 amp as quick as a 1/2 amp.

 

In other words, I wouldn't worry too much about using a 2 amp fuse.

[+TeeEff]

All very well to ask here for opinions, however, since your 60C is still under warranty I would contact Garmin and use what they say. They're the experts and also the decider of what they will and won't cover under warranty. It never hurts to get a second opinion, but that opinion should be Garmin's. Better safe than sorry.

 

Just my $.02 (or $0.0162 in Euros).

[+WeatherMaker]

Fuses are there more to protect your electrical system from a short in your device than to protect your device from a problem with your electrical system.

 

That being said, a 12 VDC car can handle 2 amps with no problem.  If you have a short in your 60CS it will blow a 2 amp as quick as a 1/2 amp.

 

In other words, I wouldn't worry too much about using a 2 amp fuse.

All very true. Even more strictly speaking, fuses are to protect the wiring, not the device. But that's not what people worry about Anyway, my thinking is that (1) a 2 amp fuse is better than none, and (2) if you gotta buy a fuse, might as well get a smaller one.

 

At least you're thinking ahead.