Hey all,

So I noticed recently that my CBI SPD only has 1 of the lights lit - the other is no longer lit like when it first was installed.

I am no sparky, so not sure whether the light itself just died (does this even happen) and the SPD is fine or whether I should look at replacing the SPD with a new one?

 

Just a plain DB board fed from Eskom only.

4 minutes ago, Superfly said:

Weird that the N pole died and the L1 is alive and kicking - I suspect a globe died  but you want proper info from it. So yes replace it with a dual pole - (Never seen them separated like that)

Thanks, will look at replacing it.

 

Does the SPD not work as a fuse of sorts as well, in the sense that if it were to die then there would not be any power output?

That is what threw me off with only the one light working.

8 hours ago, PsyCLown said:

So I noticed recently that my CBI SPD only has 1 of the lights lit

Mine recently did the same:

I also thought it very strange that the neutral pole would have experienced a surge and not the live, so I figured there's a very high chance it's just the indicator light that blew.

I replaced it just to be safe, but now that I see another case of this happening I'm again scratching my head wondering what's really going on here.

On 2023/05/09 at 11:13 PM, PierreJ said:

Mine recently did the same:

I also thought it very strange that the neutral pole would have experienced a surge and not the live, so I figured there's a very high chance it's just the indicator light that blew.

I replaced it just to be safe, but now that I see another case of this happening I'm again scratching my head wondering what's really going on here.

Quite bizarre, I'd even imagine the light is the same on both poles so I doubt it would be poor components / design flaw / bad batch.

According to SANS 10142 it needs to be replaced .

Be careful your insurance company wont pay you out if the SPD's arent working.

I replaced a double pole spd with two single pole SPD's. Can it be done? The neutral sides light doesn't light up.? 

 

On 2024/10/18 at 11:47 AM, Sarel Hietbrink said:

I replaced a double pole spd with two single pole SPD's. Can it be done? The neutral sides light doesn't light up.? 

Sarel I,ve never seen a single surge protection before,I'm sure you have to use a 2 pole(live and neutral)

I'm not sure

Edited October 22, 20241 yr by Clint

Do you have to replace the SPD completely or can you just replace the cartridges? Fivestar, Benny and Chint have removable cartridges. Then of course can you even find spare cartridges in South Africa?

More questions about SPD's. From what I can find out you need type 2 SPD's in very close proximity to your inverter. On the AC and DC inputs. You also need a type 1 to protect everything incoming in your main DB box.

I have 3 phase power coming into my property. This needs a 4 pole SPD.

But this has 40/385 on it. I think that is 40KA and 384V limiting into my house? If I tap off from one line and the neutral I get my 230V to 250V into my house (Depending on Eskom's mood) So does this tell me I'm still going to get anything below 385V into my TV and computer?

1 hour ago, Worlock said:

So does this tell me I'm still going to get anything below 385V into my TV and computer?

Spd is not an over voltage protection device, therefore you need a seperate over/undervoltage protection relay.

The attached SPD spesifications:

Model: NU6-IIG 40/385 Type 2 SPD

Type: Type 2 (Class II) Distribution board protection

Uc: 385V AC Maximum continuous operating voltage

In: 20 kA Nominal discharge current (8/20µs) wave

Imax: 40 kA Maximum discharge current (8/20µs) wave

Up: 1.8 kV Voltage protection level

Suitable for 400V 3-phase TN systems

Installed in distribution boards

Protects against:

Switching surges

Indirect lightning surges

Not suitable as a Type 1 lightning arrester for direct lightning strikes (unless combined with Type 1 upstream) Suitable for 400V 3-phase TN systems installed in distribution boards. Protects against: Switching surges indirect lightning surges.

So what voltage does it start clamping at?
That’s determined by the varistor voltage, which is not printed on the case.
Clamping behaviour is described by:
Up = 1.8kV
This is the voltage protection level during a surge (measured at In = 20kA, 8/20µs waveform).
Meaning: When a surge happens, the voltage seen downstream should not exceed about 1.8kV.

Thank you @TaliaB. I read you response carefully but with my rudimentary understanding of protection devices I'm still lost. Do I understand correctly that I must have a device similar to the above Chint but it must be a type 1 version and then another separate over/under-voltage protection relay/smoother unit? All of this in my already overcrowded main DB box.

To make matters even more complex I have two further 3 phase Sub Boards and then at the end of the string a small single phase DB board for a small loft room/flat. Must they all have these devices installed or will the one set in the main DB board suffice?

9 hours ago, Worlock said:

Thank you @TaliaB. I read you response carefully but with my rudimentary understanding of protection devices I'm still lost. Do I understand correctly that I must have a device similar to the above Chint but it must be a type 1 version and then another separate over/under-voltage protection relay/smoother unit? All of this in my already overcrowded main DB box.

To make matters even more complex I have two further 3 phase Sub Boards and then at the end of the string a small single phase DB board for a small loft room/flat. Must they all have these devices installed or will the one set in the main DB board suffice?

Main DB (most important point)
If you have overhead supply or high lightning risk, install a Type 1+2 SPD in the main DB.
If supply is underground and lightning risk is low, a good Type 2 SPD is usually sufficient.
Also install one 3-phase over/under-voltage monitoring relay with a contactor in the main DB.
This protects against: Neutral loss Phase imbalance Sustained overvoltage
You do NOT need a voltage relay in every sub-board.
Sub-boards
If the cable run from the main DB is short (<15–20m), the main SPD is normally enough.
If the run is long (>20–30m), install a Type 2 SPD in that sub-board because long cables can develop surge voltage.
Small single-phase DB at the end of a long run
If it’s far from the main DB, install a small 1P+N Type 2 SPD. No need for Type 1 there.
Bottom line:
Protection is about zoning, not duplication.
Main DB = primary protection.
Add SPDs downstream only where cable length justifies it.

4 hours ago, TaliaB said:

Sub-boards
If the cable run from the main DB is short (<15–20m), the main SPD is normally enough.
If the run is long (>20–30m), install a Type 2 SPD in that sub-board because long cables can develop surge voltage.

I have an SPD in the main DB. I asked about the sub DB but the electrician said it wasn't necessary.

But from the sub DB there is another cable (underground) to the swimming pool. Now when these surges happen they don't care which way they go. So ISTM that a surge could travel through the swimming pool cable back to that sub DB. Or is this a long shot?

1 hour ago, Bobster. said:

I have an SPD in the main DB. I asked about the sub DB but the electrician said it wasn't necessary.

Surge protection is about voltage differences between earth points.

If: Main DB earth and pool earth rise to different potentials during a lightning event that voltage difference is what damages equipment. If the loop resistance between main db and sub db is negligable then jou are good. From traveling back to the sub through the cable is possible but unlikely.

That’s why good bonding and low earth resistance matter more than just adding devices.

34 minutes ago, TaliaB said:

Surge protection is about voltage differences between earth points.

Thanks for the explanation.

On 2026/02/20 at 7:15 AM, TaliaB said:

Also install one 3-phase over/under-voltage monitoring relay with a contactor in the main DB.

Thanks again @TaliaB Can you suggest a make of the above item? I would really appreciate that.

5 hours ago, Worlock said:

Thanks again @TaliaB Can you suggest a make of the above item? I would really appreciate that.

I have use this Chint unit in the past and is performing as expected. This unit is rated for maximum 100A output so no need on this model to pair it with a contactor. Three phase application.

Brite Lighting

Chint OV/UV/OC Protector 1-63A 3P+N.Default Title

The NJVA1 voltage and current protector is a new type of intelligent protector. The product adopts a modular design; and can adjust the circuit overvoltage; undervoltage; and overcurrent. The protecto

Below single phase device Rated for 80A loads.

https://keyelectric.co.za/shop/chint-over-under-voltage-relay-80a-1pn-bottom-entry/?gad_source=1&gad_campaignid=23150872983&gclid=CjwKCAiAzOXMBhASEiwAe14SaetKBoCd8Vbs5OoCMxUFJUjSDhqi3dS1I1eDqc71shHY2ZFwd8pVgBoCAkwQAvD_BwE

I'm a total noob to this. Is a single pole without neutral sufficient or should a double pole with neutral be installed. Insurance companies are now demanding a 40ka surge protector be installed.

2 hours ago, Paul459 said:

I'm a total noob to this. Is a single pole without neutral sufficient or should a double pole with neutral be installed. Insurance companies are now demanding a 40ka surge protector be installed.

Below link what SPD you need to purchase and get installed by a electrician. SPD'S are connected to live and neutral on top and earth at the bottom to your main db earth connection.

ZJ Beny AC Surge Arrestor 2Pole SPD 275VAC 40KA for Sale...

Buy ZJ Beny AC Surge Arrestor 2Pole SPD 275VAC 40KA online in South Africa. The Herholdts' Group offers a wide range of ZJ Beny. We offer courier delivery Nationwide. Order yours Today!

3 minutes ago, TaliaB said:

Below link what SPD you need to purchase and get installed by a electrician. SPD'S are connected to live and neutral on top and earth at the bottom to your main db earth connection.

ZJ Beny AC Surge Arrestor 2Pole SPD 275VAC 40KA for Sale...

Buy ZJ Beny AC Surge Arrestor 2Pole SPD 275VAC 40KA online in South Africa. The Herholdts' Group offers a wide range of ZJ Beny. We offer courier delivery Nationwide. Order yours Today!

Thanks man , appreciated

Is there a CBI equivalent?

1 hour ago, Paul459 said:

Is there a CBI equivalent?

Yes quite expensive. Imax 40 kA (8 / 20 μs) Surge Protection Device Part No: QKLN-2(13)D 1 pole and neutral 275 V, with indication. Order No : QKLD0002. You can source it from electrical outlet in your vicinity.

Edited March 3Mar 3 by TaliaB

Key Electric Online

CBI 1P+N Surge Protector (CBI SAM / QKLN‑2(13) Mini Rail)

CBI 1P+N Surge Protector (CBI SAM / QKLN‑2(13) Mini Rail)

2 hours ago, TaliaB said:

Key Electric Online

CBI 1P+N Surge Protector (CBI SAM / QKLN‑2(13) Mini Rail)

CBI 1P+N Surge Protector (CBI SAM / QKLN‑2(13) Mini Rail)

Last question. The CBI is 1 Pole compared to the Beny which is 2 Pole. Will the 1 Pole place me at a disadvantage?

5 hours ago, Paul459 said:

Last question. The CBI is 1 Pole compared to the Beny which is 2 Pole. Will the 1 Pole place me at a disadvantage?

I would always go for the 2 pole to protect live and neutral. The CBI part number is a 2 pole as illustrated in the link. Both the Beny and CBI is 2 pole only diffrence is price.