Surge Guard - anyone used them?

[Moody Blue]

Found these at a local discount store. Calterm SurgeGuard. Claims to protects 12V electrical components/systems from voltage spikes by "sending the excess voltage to ground". It connects directly across the two battery terminals.

Looking for feedback from anyone that has used them. Gimmick or not?

 

[Silvertip]

Re: Surge Guard - anyone used them?

What voltage is it set for?

 

[Moody Blue]

Re: Surge Guard - anyone used them?

No settings on it. Plug and play "12V".

Has a flashing LED that indicates the device is operating properly.

 

[Silvertip]

Re: Surge Guard - anyone used them?

I didn't mean did it have any adjustments. In order to "protect" a 12 volt system the device needs to have a threshold voltage somewhere in the upper end of a typical 12 volt systems operating range which would be 12.6 to about 14.5 volts. If the trigger point for the device is at the low end of the range, the charging system is deprived of doing it's job. The voltage regulator on the engine has the job of regulating system voltage. The only use I could see for this device would be on an older engine that does not have a voltage regulator.

 

[Moody Blue]

Re: Surge Guard - anyone used them?

No idea what that value would be. No other info available on the packaging or on-line that I could find. A mystery device.

I have a 71 Merc 800 without any kind of regulation, other than the battery itself. I know the switchbox is susceptible to overvoltage and thought this little device may help protect it.

Not sure if it is a true surge protector (short duration high voltage spike) or some kind of voltage limiting device.

 

[bruceb58]

Re: Surge Guard - anyone used them?

It doesn't have to have a threshold. Probably just passive components. Spikes have a failry high frequency component to them so it is just a matter of selecting components to get the correct time bandwidth of the filter. Basically...its just a simple low pass filter.

If you really want to protect your electronics, you should really be using an inline low pass filter made with inductors. I have made many of those myself.

This device mentioned will not protect against overvoltage if the overvoltage is DC...only spikes.

 

[bruceb58]

Re: Surge Guard - anyone used them?

I found it:

http://www.amazon.com/Surge-Guard-Protects-Vehicle-Systems/dp/B0000AXFTZ

Looks pretty worthless to me.

 

[Moody Blue]

Re: Surge Guard - anyone used them?

Yep, that's it. Not currently available that I could find anywhere on-line so must have been a flop product.

What is my best bet for protecting against overvoltage?

 

[Silvertip]

Re: Surge Guard - anyone used them?

Seems to me the statement "shorting to ground" is hardly a passive device.