Toggle Switch

[CookieOldParticipant @cookieold]

[CookieOldParticipant @cookieold]

Hi All , Could anyone please advice me on toggle switch specs with regards to when it states 10amp max current does this mean switching current and if so are they able to coup with a far greater current flowing through then when not switching.

Regards Dave

[Malcolm FraryParticipant @malcolmfrary95515]

The figure quoted is normally the carrying current. It is good sense to do a bit of derating if only to give the switch a longer lifetime and allow for switching surges. In model boat use, a switch like that would be for main power – it would only switch a large current if the motors were powered in stall conditions at switching. This should never happen.

Occasionally a switch will be quoted with differing current ratings at different voltages, usually a lot lower at higher voltages. This is to allow the contacts to survive better when switching what might be an inductive load off. You can get some fearsome voltages generated that way. While the contacts are separating, arcing can happen, which shortens the contact life.

[CookieOldParticipant @cookieold]

Hi Malcolm , Thanks for the reply , I just wanted to isolate my bats with a switch it,s a big boat with 3 motors with a total of about 25 amps , but stall amps fare higher , have you any ideas .

Best Regards Dave

[Charles OatesParticipant @charlesoates31738]

Hi cookie, if you are just isolating the motors / battery rather than switching a current, surely a small, say 10 amp switch will do the job. I’m suposing that no current is flowing when the switch is moved.
Chas
of course the guessing that the contacts in the switch will carry the current without heating.

Edited By Charles Oates on 29/10/2014 23:57:53

[CookieOldParticipant @cookieold]

Hi Charles , Yes you are currect no current will be flowing when switching but is it not as Malcolm says that the figure quoted is the current flow max , I hope you are right and Malc is wrong as that would solve my problem.

Best Regards Dave

[Charles OatesParticipant @charlesoates31738]

Hi again, I’m sure Malc is correct, it’s just that there is a difference between carrying a current through the contacts, and switching the current. If this were my model I’d be using the highest rated switch I can find. Playing safe is best.

[TelstarParticipant @telstar]

Hi Charles, Dave. Malcolm is exactly right. The normal rating figures are the Max. current to flow in the device and the Max. voltage the device can safely work at. these are not interdependent ie. using a lower voltage does NOT mean you can use a higher current. Dependant on the construction of the switch, a high current can overheat the contact area causing the switch to loose contact pressure and spark, effectively killing the switch.

Some devices do give switching ratings usually for ac use and dc use, or state ac use only' again this is the manufacturers recommendation for reliable use.

This does not mean you have to accept these figures, only that disregarding them will cause premature failure of the device

To Isolate the battery, is it feasible to have a removable fuse link in each battery lead (there should be some kind of protection) and remove these to isolate the battery.

Cheers Tom

[Charles OatesParticipant @charlesoates31738]

Thanks Tom, much clearer than I could ever be.
Cookie, have you considerd a shorting plug, this is just a simple suitably rated small plug and socket with a stout conection across the plug terminals. Just pull the plug out to isolate.
We used to use these in the very early electric planes.

[Dave MilbournParticipant @davemilbourn48782]

**LINK**

**LINK**

As advertised in Model Boats magazine.

[Author]

Posts