Does a circuit board with an SPD protect against internal surges?

[oscarelectrics]

Hello!

I'm struggling to find an answer to this question online. I'm new here btw - I'm a DIYer with a physics degree

Currently when my fridge motor turns off, I get a transient voltage spike on other devices plugged into the same circuit (i.e. an internal surge)

If I upgraded my circuit board to include an SPD, would this help prevent this and dissipate the energy? Or does it only protect against lightening strikes and similar external spikes?

Thanks!
Oscar

 

[oscarelectrics]

Hello!

I'm struggling to find an answer to this question online. I'm new here btw - I'm a DIYer with a physics degree

Currently when my fridge motor turns off, I get a transient voltage spike on other devices plugged into the same circuit (i.e. an internal surge)

If I upgraded my circuit board to include an SPD, would this help prevent this and dissipate the energy? Or does it only protect against lightening strikes and similar external spikes?

Thanks!
Oscar

By the way I'm talking about buying a new circuit board with a SPD, eg from screwfix

 

[pc1966]

Yes - to a degree.

The SPD in the CU will clamp the voltage there to somewhere in the region of 400V-1.4kV depending on the surge current. But if you have a fast surge (high dI/dt) then the impedance of the wring will limit how well the SPD at the CU can limit the voltage at the source of the disturbance.

For a specific appliance that is causing trouble to its neighbours on the same circuit you might be better to consider a plug with SPD built in:

https://cpc.farnell.com/pro-elec/9518s/plugtop-surge-protected-13a/dp/PL10022

Note: such a plug has limited capacity for surges, it won't help much if you get a few kA from lightning nearby!

 

[pc1966]

If you are interested this has lots of related info:

https://www.nvent.com/sites/default/files/acquiadam/assets/E907W-WWEN.pdf

 

[oscarelectrics]

Thanks!

That's an interesting device you've linked. I'm familiar with power outlets (eg 4 way power outlets) that have built in surge protection. But that device doesn't seem to have something you can plug into? So I'm guessing you plug this into the same circuit as the troublesome appliance, and then it dissipates any excess energy when it detects a spike? Or am I being slow?

 

[DPG]

Thanks!

That's an interesting device you've linked. I'm familiar with power outlets (eg 4 way power outlets) that have built in surge protection. But that device doesn't seem to have something you can plug into? So I'm guessing you plug this into the same circuit as the troublesome appliance, and then it dissipates any excess energy when it detects a spike? Or am I being slow?

It's a 13A plug with surge protection built in - replace the normal 13A plug with this.

 

[Avo Mk8]

Thanks!

That's an interesting device you've linked. I'm familiar with power outlets (eg 4 way power outlets) that have built in surge protection. But that device doesn't seem to have something you can plug into? So I'm guessing you plug this into the same circuit as the troublesome appliance, and then it dissipates any excess energy when it detects a spike? Or am I being slow?

I believe it's a plug you put on the flex of the appliance you need to protect (Instead of a normal 13A plug)!
as above -DPG beat me to it! Doh! Must pay more attention to what's been posted

 

[oscarelectrics]

Oh I see! I guess I'm showing my age. Wiring a plug is not something I've ever had to do. Ha!

 

[pc1966]

You can also plug it in to the adjacent outlet of a double socket (if free) and that way you don't have to cut off the moulded plug to fit it.

 

[DPG]

You can also plug it in to the adjacent outlet of a double socket (if free) and that way you don't have to cut off the moulded plug to fit it.

Must admit I've never thought of using them like that. Not a bad idea.

 

[oscarelectrics]

Brilliant, thanks everyone for the great suggestions

 

[DPG]

Brilliant, thanks everyone for the great suggestions

Let us know how you get on.

 

[oscarelectrics]

So is that better than using something like this? Does a circuit board with an SPD protect against internal surges? - https://www.electriciansforums.net/threads/does-a-circuit-board-with-an-spd-protect-against-internal-surges.208688/#post-1833953

 

[James]

Hello!

I'm struggling to find an answer to this question online. I'm new here btw - I'm a DIYer with a physics degree

Currently when my fridge motor turns off, I get a transient voltage spike on other devices plugged into the same circuit (i.e. an internal surge)

If I upgraded my circuit board to include an SPD, would this help prevent this and dissipate the energy? Or does it only protect against lightening strikes and similar external spikes?

Thanks!
Oscar

Although a surge protector is a good idea to protect against unexpected surges that may damage electrical devices,

You seem to have a device with a known fault (fridge) in that when it is switching on/off it is putting electrical surges or noise in the local distribution of your property and/or electrical noise passing through the air.

Really you should be looking to remove the interference at source, not trying to suppress it after the event.
A new fridge might be the best option for you.

 

[oscarelectrics]

Woops wrong link! I meant, would it be better than something like this? https://cpc.farnell.com/pro-elec/97...9208&s_kwcid=AL!5616!3!491098866149!!!network}!887692084055!&gclid=CjwKCAjwt52mBhB5EiwA05YKo2SXjW3fdgcvkcsr8fXBp_AAv5hVnTBgEvoqPL_B871SMrQlZj-vxBoCnXQQAvD_BwE

 

[James]

If a car that has been working fine for years suddenly starts pouring smoke out and disturbing the neighbours, do we

A.. Find a way to mask the neighbours from the smoke using shields and filters so they don't notice?
or
B.. Fix the car so it no longer disturbs them with plumes of black smoke every time you start it up in the morning.

 

[oscarelectrics]

If a car that has been working fine for years suddenly starts pouring smoke out and disturbing the neighbours, do we

A.. Find a way to mask the neighbours from the smoke using shields and filters so they don't notice?
or
B.. Fix the car so it no longer disturbs them with plumes of black smoke every time you start it up in the morning.

Yes good point taken... Fridge will be replaced in a few months, but keen to protect against damage in the meantime, and in general upgrade the electrics here! Thanks

 

[oscarelectrics]

If a car that has been working fine for years suddenly starts pouring smoke out and disturbing the neighbours, do we

A.. Find a way to mask the neighbours from the smoke using shields and filters so they don't notice?
or
B.. Fix the car so it no longer disturbs them with plumes of black smoke every time you start it up in the morning.

Yes good point taken... Fridge will be replaced in a few months, but keen to protect against damage in the meantime, and in general upgrade the electrics here! Thanks

 

[davesparks]

Yes good point taken... Fridge will be replaced in a few months, but keen to protect against damage in the meantime, and in general upgrade the electrics here! Thanks

Have you considered a repair rather than replacement, this problem could be the result of a simple component failure.

 

[oscarelectrics]

The fridge is already rusty on the outside etc so i think it's part its shelf life...