ChatterBank1 min ago
Electric Tripping
15 Answers
Hi, I asked this question but don't think it submitted so here goes, my switchboard under the stairs seems to be really sensitive In april I had a diagnosis from a British Gas sparky for my garage which kept tripping when the drier was on, he said it was the wire under the patio worn out and I would need a new one (600 so will have to wait) my homecare only covers above ground.
Anyway roll on July when I knocked my extension tower connecting my computer to the wall socket in the living room, it fell with a bang and again knocked off the inside trip switch it did this twice so I removed tje tower no problems, today my landline handset became faulty I put it on the handset again tripped the switchboard. Is this over sensitivity normal? Or is there another issue causing this.
Anyway roll on July when I knocked my extension tower connecting my computer to the wall socket in the living room, it fell with a bang and again knocked off the inside trip switch it did this twice so I removed tje tower no problems, today my landline handset became faulty I put it on the handset again tripped the switchboard. Is this over sensitivity normal? Or is there another issue causing this.
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Could be different things. You need the electrician to check the house wiring in general to ensure it's up to scratch. Your tower thing might have an issue. The drier also.
Is it the miniature circuit breakers or the residual current detector that goes ?
No normally it ought not be sensitive though. Must be one or more issues.
Is it the miniature circuit breakers or the residual current detector that goes ?
No normally it ought not be sensitive though. Must be one or more issues.
It's the main green trip switch that goes off whenever anything has a fault. So my phone had a fault and when it was replaced on the handset, it tripped the green socket switch under the stairs, the tower fell over, also tripped it. Both these have been removed and the mains is ok. I am just concerned that such small things are causing the mains switch under the stairs to go off so easily
These units are designed to trip if they detect any electrical current leaking to earth. As you have told us you have a worn wire that could be causing the trips. My circuit breaker trips if even a light bulb blows.
They are designed to be sensitive as they are a safety warning of potential problems.
They are designed to be sensitive as they are a safety warning of potential problems.
The worn wire is the one going to the detached garage to the house, this has now been completely disconnected at the switchboard and I need a new wire fitting. There is no power to the garage as a result of this. It just seems strange that now my house trips from the smallest of faults at the sockets.
As other have said, you need to get the electrics checked out by an electrician.
Eddie51 posted that these units are designed to trip if they detect any electrical current leaking to earth. This is not quite so – normal domestic devices will have a trip current set at 30mA to allow for the normal earth leakage of individual appliances.
Before you pay out for the services of an electrician, I would try switching off one of the circuits supplied from the consumer unit in turn. If the system does not trip with a particular circuit switched off, then it is very likely that the fault is in this circuit.
I have seen such a problem to be due to a fault in the home heating system (either the immersion heater or pump) – and with a kettle.
Not having the problem fixed (besides being a nuisance), could result in your fridge/freezer being off for an extended period, spoiling the food.
Eddie51 posted that these units are designed to trip if they detect any electrical current leaking to earth. This is not quite so – normal domestic devices will have a trip current set at 30mA to allow for the normal earth leakage of individual appliances.
Before you pay out for the services of an electrician, I would try switching off one of the circuits supplied from the consumer unit in turn. If the system does not trip with a particular circuit switched off, then it is very likely that the fault is in this circuit.
I have seen such a problem to be due to a fault in the home heating system (either the immersion heater or pump) – and with a kettle.
Not having the problem fixed (besides being a nuisance), could result in your fridge/freezer being off for an extended period, spoiling the food.
I'll assume that the green switch is the RCD. That means, as Eddie says, you have a earth issue. It will trip as soon as it detects the current flowing in is different to the current flowing out. It monitors the total current not current to individual equipment. Any appliance with an earth leakage fault will turn off everything connected to the RCD.
Good luck finding and replacing the dodgy items. Or the sockets/cables.
Good luck finding and replacing the dodgy items. Or the sockets/cables.
Most appliance safety standards allow an earth leakage current of up to 3.5mA – this leakage current (to earth) is mostly a component of the mains filtering within the appliance.
Although most appliances will have a normal earth leakage current well below 3.5mA, to avoid nuisance tripping the consumer unit total earth leakage trip current is set at 30mA.
Although most appliances will have a normal earth leakage current well below 3.5mA, to avoid nuisance tripping the consumer unit total earth leakage trip current is set at 30mA.
I don't think you have a problem, both times you say it tripped there was an actual fault !, the tower falling would have caused a momentary power surge or earth leak and your landline handset did have a fault.
As the wire to the garage is now disconnected you should now be clear of faults. Just see if there are any more trips.
As the wire to the garage is now disconnected you should now be clear of faults. Just see if there are any more trips.
When was the system last tested.The RCD should be tested at 50% rated operating current...on the upper and lower side of the a.c. sine wave(if yours is rated at 30mA then a 15mA test will be performed)and the device should NOT operate.If it does then its no good.The third test is at rated current again on both 0 deg and 180 deg of the sine wave and the device should operate.The fifth test is at 150mA again on both sides of the sine wave and the device should operate within 40 Ms.Sound complicated but most testers do it on auto so its easy.If future unwanted tripping occurs with no good reason then get a decent sparks in.
You've been given some excellent advice by others already, but I just wanted to add a couple of things...
Earth leakage is cumulative. That is, each appliance may have natural leakage (as explained above.) Anything to do with water heating are often guilty. All these small currents add up until a point is reached when the RCD will operate.
On a standard 30milliamp RCD, this is actually around the 23-24 milliamp level. Quite normal. You may have reached this point for one reason or another.
RCDs do not last forever. I have come across this before. In those cases, I ran what is known as a "ramp test." This is a very quick and easy test on a "Megger". It simply ramps up the current slowly until the point is reached where the RCD trips. I have found trips that operated at around 12-15 milliamps. Far below their original design value. Replacing the RCD and re-testing fixed that.
But, before blaming the RCD for over-insensitivity, I would certainly look at the whole installation for possible leakage faults.
Earth leakage is cumulative. That is, each appliance may have natural leakage (as explained above.) Anything to do with water heating are often guilty. All these small currents add up until a point is reached when the RCD will operate.
On a standard 30milliamp RCD, this is actually around the 23-24 milliamp level. Quite normal. You may have reached this point for one reason or another.
RCDs do not last forever. I have come across this before. In those cases, I ran what is known as a "ramp test." This is a very quick and easy test on a "Megger". It simply ramps up the current slowly until the point is reached where the RCD trips. I have found trips that operated at around 12-15 milliamps. Far below their original design value. Replacing the RCD and re-testing fixed that.
But, before blaming the RCD for over-insensitivity, I would certainly look at the whole installation for possible leakage faults.
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