Daniel DD
DIY
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BACKGROUND
I live in a small town where it is difficult to find ceritified electricians. In fact, electrician certification is not common for residential installations. I did find some experienced electricians but I don't think they are certified and know best practices in the installation.
I reached out to the company for support but the technical assistance on the products are limited and I need further clarification to make sure that I purchase the correct products and the installation is safe.
NOTE
I WILL NOT do the installation by myself. I WILL CERTAINLY hire an experienced electrician after getting enough information.
I have questions on the surge arrester/surge protection device (SPD), contactors, and control relays. I will start with a post about the SPD.
PROBLEMS
I am going to install a surge arrester to the home main panel. I prefer not to break the concrete wall and not to change the existing wiring buried in it.
The voltage input ranges from 220 V to 230 V. The neutral line from the power meter does not light up the tester screw driver (it is grounded by the power company) and my house has its own separated grounding rod so I think it is the TT grounding system.
The wiring is shown in the picture below.
Here are my questions:
1. Schneider recommends that an external Short Circuit Protection Device (SCPD) (3), which has the rated current of 40 A, be installed with the surge arrester (5), which has the Imax of 40 kA.
It is important to use the SCPD tested by the company as one of the essential characteristics of SCPD is that it withstands
the lightning current and must not trip upon 15 successive impulse currents at the nominal current.
The MCB installed by the power company (1) has the nominal current of 20 A which is related to 4400 VA consumer power subscription. This MCB can be a product of Schneider or ABB depending on the stock.
If a lightning surge flows through the power lines and reach the 20 A MCB (1), considering that this MCB is not the one recommended by the company and it has a lower rated current compared to the SCPD (3), will this disrupt the function of the surge arrester(5)?
2. The SPD installation must comply with the 0.5 - meter rule. To reduce the length of the wire conductors, a busbar rated 100 A is used to connect the SCPD (3) and the RCCB (4) so only the length of the wires labeled A and B are subjected to rule.
Can the length of A and B be as short as possible or there is a minimum safety distance between the bottom terminals of SCPD (3) and the top terminals of the surge arrester (5), likewise, between the bottom terminals of the surge arrester (5) and the top terminals of the ground terminal block (6)?
3. Schneider mentions that the incoming polluted and the outgoing clean cables must be physically separated. Is there a minimum distance, labeled C, D, E, F, between cables to minimize the effect of the electromagnetic coupling in the event of lightning surges?
I live in a small town where it is difficult to find ceritified electricians. In fact, electrician certification is not common for residential installations. I did find some experienced electricians but I don't think they are certified and know best practices in the installation.
I reached out to the company for support but the technical assistance on the products are limited and I need further clarification to make sure that I purchase the correct products and the installation is safe.
NOTE
I WILL NOT do the installation by myself. I WILL CERTAINLY hire an experienced electrician after getting enough information.
I have questions on the surge arrester/surge protection device (SPD), contactors, and control relays. I will start with a post about the SPD.
PROBLEMS
I am going to install a surge arrester to the home main panel. I prefer not to break the concrete wall and not to change the existing wiring buried in it.
The voltage input ranges from 220 V to 230 V. The neutral line from the power meter does not light up the tester screw driver (it is grounded by the power company) and my house has its own separated grounding rod so I think it is the TT grounding system.
The wiring is shown in the picture below.
Here are my questions:
1. Schneider recommends that an external Short Circuit Protection Device (SCPD) (3), which has the rated current of 40 A, be installed with the surge arrester (5), which has the Imax of 40 kA.
It is important to use the SCPD tested by the company as one of the essential characteristics of SCPD is that it withstands
the lightning current and must not trip upon 15 successive impulse currents at the nominal current.
The MCB installed by the power company (1) has the nominal current of 20 A which is related to 4400 VA consumer power subscription. This MCB can be a product of Schneider or ABB depending on the stock.
If a lightning surge flows through the power lines and reach the 20 A MCB (1), considering that this MCB is not the one recommended by the company and it has a lower rated current compared to the SCPD (3), will this disrupt the function of the surge arrester(5)?
2. The SPD installation must comply with the 0.5 - meter rule. To reduce the length of the wire conductors, a busbar rated 100 A is used to connect the SCPD (3) and the RCCB (4) so only the length of the wires labeled A and B are subjected to rule.
Can the length of A and B be as short as possible or there is a minimum safety distance between the bottom terminals of SCPD (3) and the top terminals of the surge arrester (5), likewise, between the bottom terminals of the surge arrester (5) and the top terminals of the ground terminal block (6)?
3. Schneider mentions that the incoming polluted and the outgoing clean cables must be physically separated. Is there a minimum distance, labeled C, D, E, F, between cables to minimize the effect of the electromagnetic coupling in the event of lightning surges?
- TL;DR
- 1.During a lightning surge, if the power meter has an MCB with a rated current lower than that of the MCB dedicated to the SPD, will this disrupt the function of SPD?
2. Is there a mininum safety distance between two MCBs installed vertically and between polluted incoming and clean outgoing cables?
