Home power intermittently tripping

[devion]

Recently my RCCB keeps keeps tripping intermittently. It can happen between several hours to few days when a trip will occur. During the trips, no additional appliances were switched on or being used. There are times when it simply trips in middle of night when most appliances are not running.
There are also times when the trips can happen successively a few times in a minute but was able to recover after several resets.
So far am able to reset the RCCB all the time.

On few occasions, one of my MCBs also tripped & this helped me to suspect the issue could be isolated to one of my rooms. However in most cases only the RCCB trips, hopefully the occasional MCB tripping is not leading me to a wild goose chase.

With this, I had to switch off each devices in this room connected to the tripped MCB & monitor several days if trips been resolved.
Reading few blogs, MCB trips could be due to faulty appliance or overloading.
In this room, I have 3 PCs, 1 router & 3 handphone chargers plugged in into 2 socket outlets with 2 multiple sockets extension. I had this connection for several months w/o power trips which is why I am not suspecting overloading here.
In some instances of power trips during the nights, PCs & chargers are not in used, although power was not switched off for the chargers. Only the router is turned on all this time.
if faulty appliance, I would expect the trips would be almost immediate & not so intermittent.

Was hoping to find out any quick method to determine which of this is the cause of the intermittent trips other than isolating one each time & monitor several days.
Another suspect could be the RCCB itself although this would cost me to purchase a new one or engage a licensed electrician to fix it.

 

[DPG]

If the MCB is tripping then you potentially have quite a serious fault. I would definitely get an electrician in to look at this. Someone with the proper test equipment will be able to narrow things down.

 

[Vortigern]

Do you have a rodent problem?

 

[devion]

Do you have a rodent problem?

Definitely not, am staying in a high rise apartment which is 10 years old & very clean & tidy environment.

 

[UNG]

Faulty auto defrost heater on a fridge or freezer usually causes the random tripping problem you have

 

[DPG]

Faulty auto defrost heater on a fridge or freezer usually causes the random tripping problem you have

Sounds like the MCB is tripping as well though

 

[devion]

Sounds like the MCB is tripping as well though

This was my initial suspect too as the fridge is the only high powered appliance turned on all the time. However the occasional trip on one of my MCB is not on the circuit of the kitchen. Is there a way to check whether the fridge is the culprit, it is 10yr old & I do see some sweating outside the freezer compartment, but this has been like that for past year w/o power trips.
Isolating the fridge is not a choice since I need to use it 24/7.
The intermittent trips makes it so difficult to pinpoint where exactly is the cause.

 

[DPG]

Can you use an extension cable and plug the fridge into a socket on a different circuit?

 

[devion]

Can you use an extension cable and plug the fridge into a socket on a different circuit?

I only have entire 1 circuit in my home connected to one RCCB.

 

[DPG]

I only have entire 1 circuit in my home connected to one RCCB.

Ah right. Sorry, I assumed split board.

 

[devion]

The intermittent trips still occurring, sometimes more than 12hrs apart w/o any additional appliances being used, with this am more likely now suspecting to be the fridge which is the only heavy loaded appliance operational all this while.
Only puzzling thing how it can be this intermittent as in several hours apart on the trips. Most of the trips also seem to happen during late into the wee hours, though day time does trip too.
Am thinking of getting the external power socket with a RCD, 13A Gfci Leakage Protection Plug on it to connect this to the fridge, so that if it is the cause, it will only trip this RCD instead of the entire house RCCB. This device is affordable instead of replacing entire fridge.

 

[Electro-tech]

An RCD, 13A Gfci Leakage Protection Plug may not have the selectivity to discriminate if both devices are the same mA rating. The RCCB may still trip.

 

[devion]

Prior to my new fridge which is a wait of 5 days, any idea how to overcome the regular trips during the fridge defrost heaters acting up? My trips are now abt ~11-12hrs apart which means the current defrost freq set is likely 12hrs. I was contemplating to turn the fridge power off for 60mins during those defrost cycles periods, whether this is advisable.
I was still hoping whether the external RCD socket will work though, so it only trips the fridge instead of entire house.

 

[timhoward]

I’m afraid it’s unlikely an extra RCD socket will not also trip the upstream device too.
There isn’t much you can do that is practical in the meantime.
Does your cooker switch have a socket on it? An extension lead from that might be a temporary workaround.

Getting the normal leakage current measured or the RCD ramp tested would normally be the first course of action before replacing appliances. Or did you prove beyond doubt it’s the fridge?

 

[devion]

Nope, my cooker hob is using gas. It is due to the frequent trips & the pattern that I have tracked which is very clearly that the trips occur around the ~12hrs intervals which I highly suspect its the fridge, which I read around that it has defrost times set at various intervals, some can be as long as 12hrs. My fridge is also >10 years old & some sweating seen at external freezer door, its about time to change anyways. Just that meantime, wat probable steps to take to prevent entire house to trip during the ~12hrs intervals.

 

[devion]

I managed to locate the defrost heater unit at the freezer coil area, I simply terminated one of the wires & electrically wrapped it.
Let's hope this works.

 

[devion]

I managed to locate the defrost heater unit at the freezer coil area, I simply terminated one of the wires & electrically wrapped it.
Let's hope this works.

Update, after terminating one of the defrost heater wires, my trips became more frequent. It is now every 3-4hrs compared to previous 12hrs. This is very odd....desperate to get the new fridge in which is 4 days time. My fridge I believed is auto defrost, dun see a timer circuit there, not so sure whether it is now triggering more regular defrost cycles...

 

[suffolkspark]

Update, after terminating one of the defrost heater wires, my trips became more frequent. It is now every 3-4hrs compared to previous 12hrs. This is very odd....desperate to get the new fridge in which is 4 days time. My fridge I believed is auto defrost, dun see a timer circuit there, not so sure whether it is now triggering more regular defrost cycles...

You probably disconnected the Neutral. You need both cables off the element, and terminated in something safer than tape, can you trace them back to a pcb and unplug?

 

[devion]

You probably disconnected the Neutral. You need both cables off the element, and terminated in something safer than tape, can you trace them back to a pcb and unplug?

Today I proceed to the circuit board & unplug the cables to the defrost heaters. Hope it works. Unfortunately, when I was doing this with the fridge powered off but the power plug is still plugged inside the socket, my main breaker trip!!! OMG, hopefully its the fridge & nothing else. All this while am suspecting the fridge......
If its not the fridge, my only suspect is the breaker itself....but the trips frequency is so random, sometimes with a pattern of ~12hrs apart & just yesterday, was very frequent, ~3-4hrs apart. The latest trip event 2x, was only 1/2 hr apart.
Really a mystery to solve if its not the fridge...maybe the RCCB has deteriorated after so many trips...>50 times since abt a week ago.

I contacted one of electrical company, after I told them its random & unknown root cause, he stated cannot engage them because they need the trip to occur when at the location.
Am sure more qualified electrician will be able to conduct some diagnosis of my household circuit to narrow down exact cause of the random trips.
let's see if disconnecting the defrost heater circuit will work. fingers crossed. At my wits end now, have to hunt down a good qualified electrician to remedy my random trips.

 

[suffolkspark]

Today I proceed to the circuit board & unplug the cables to the defrost heaters. Hope it works. Unfortunately, when I was doing this disconnection, I powered off the fridge with the power plug is still plugged in, my main breaker trip!!! OMG, hopefully its the fridge & nothing else.
If its not the fridge, my only suspect is the breaker itself....but the trips frequency is so random, sometimes with a pattern of ~12hrs apart & just yesterday, was very frequent, ~3-4hrs apart. The latest trip event 2x, was 1/2 hr apart.
Really a mystery to solve if its not the fridge...maybe the RCCB has deteriorated after so many trips...>50 times since abt a week ago.

I contacted one of electrical company, after I told them its random & unknown root cause, he stated cannot engage them because they need the trip to occur when at the location.
Am sure more qualified electrician will be able to conduct some diagnosis of my household circuit to narrow down exact cause of the random trips.
let's see if disconnecting the defrost heater circuit will work. fingers crossed. At my wits end now, have to hunt down a good qualified electrician to remedy my random trips.

Unplug things when your playing with them.