remote resetting of circuit breaker 1

[TheSimo]

I am trying to identify if there exists a circuit breaker capable of being reset remotely.
In my application theres not always somebody around to reset the C/B manually i.e overnight after a lightning strike.

I'm talking regarding mains power.

I am aware of auto resetting types for automotive use (12V) where a vehicles light will go on/off/on if a short exists in the vehicles wiring. Does a 240 volt equivalent exist?

 

[waross]

Yes and no.
There are "Klixon" type of overload devices that will operate on an overload and reset automatically.
Unfortunately, they themselves must be protected by a circuit breaker in most applications and they may not be available in high amperages. Another limitation is the lack of overcurrent protection. They will respond to an overload, but they will not respond to a short circuit or transient fast enough to satisfy code requirements.

The best setup for your application may be motor operators.
These are devices that fix to the front of a circuit breaker and use an internal motor and gearing to mechanically move the breaker handle. They are often used to construct transfer switches in larger sizes.

I doubt that any inspector will accept automatic resetting of a main breaker.
Consider the possible example of a worker inadvertently shorting out a panel with his tools (or part of his body).
The main breaker trips as it should only to be reset a few seconds later.

A better course of action would be to install surge suppressors and breakers that are not as suceptible to lightning induced transients.

Before considering motor operators, you would want to design a monitoring system that would ensure that the trip was related to lightning and not to a problem at the facility.
I prefer avoiding lightning trips rather than trying to automatically reset after a trip.
respectfully

 

[TheSimo]

Hello waross
Thank you I need to clarify I guess this is always the problem on a post second guessing.

OK the systemn is in a secure enclosure (padlock box) and the ELCB is being tripped regularly during storms. The system is a low current example a GSM I/O device and Paperless recorder and ultrasonic unit the total current is about 500mAmps of a 240VAC ELCB.

I was not involved in the installation of the ELCB nor the main distribution 240V which is about 100 meters away. A good earth is probably missing as it trips regularly. The project is in Malaysia and I am in OZ and will return in June2007.

I would like to improve the earth first but would like to have a toggle outside the enclosure that could reset the CB. As the GSM device will go to battery when not on AC voltage it will send an SMS to tell staff that the power has been tripped so if I can get a way to reset with out opening the enclosure it would improve security and I will be able to send an SMS to reset the breaker. If it trips a second time will send staff at that point.

Thats the scenario I am aiming for.

regards
Simo

 

[waross]

Hi simo;
I am not sure of the meaning of all of your abreviations.
But, Is the 100 meters above ground or underground?
Try supressors on the main service. If you can strap ferrous conduits together and run each conductor in a seperate conduit it will present a very high impedance to steep wave front transients such as lightning induced surges. Put it on the load end of your conductors so as to use the resistance of the feeders to help absorb surges.
If your codes will allow it, replace the Earth Leakage Circuit Breaker with a standard breaker.
respectfully

 

[TheSimo]

This area is large water reservoir tanks and I data log level and send 96 readings in one SMS to graph the daily level changes. Their are alarm points so they do not overflow as these tanks are in the jungle up top of a hill or backend of a small mountain (gravity water feed method)

Copper used in earthing is of great theft value so some time it gets stolen Your suggestion to not earth the enclosure end is in my way of thinking as well on this situation.

As to the wire above or below YES each site varies so over some under. It looks to be a case by case situation. i have found basic MOV (metal oxide varactors to be helpful as well but they do not last long.

regards
John

 

[itsmoked]

Bill; SMS - Short Message Service. Cellphone back data channel messaging.

The Simo; Sounds like a fun one. How about ground rods with lightning arrestors to shunt surges to ground.

Curious, could the system stand to be shut off during any particular storm?

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[TheSimo]

Itsmoked

Thanks yes I think the other side is to increase the arth rods to get a better earth at the distribution panel and the enclosure box (100meter seperation mostly overhead 240V)

The SMS unit is a Cyplex Packetiser.

In one sense it could be trned off The packetiser will be on battery but not run the ultrasonic unit so I would have no measurements and they are after 15 minute intervals on level!

Lightning storms in Malaysia are intense and the normal power is noisy. The other issue is when large building or factories are being built they seem a bit lacks when welding.

Thanks to all its looks like i need to solve the surge spikes and filter them to avoid the relay technique I am looking for.