Protection relay requirements

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SS_EE

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Hi,
Could someone please let me know on the following:
For a grid connected PV system do we require to use a protection relay for the main breaker before tapping to the client's main distribution board, since the current inverters generally come with in-built AC overcurrent protection, surge arrestors etc.? if additional relays required could you please refer me the exact code which mentions the protection requirements for distribution energy resources?

Thanks in advance for your answers
 
In the US a protection relay would be a utility requirement. It would not be an electrical code requirement. Is the utility asking for a relay? Have you applied to the utility for approval to interconnect the system? How big a system are we talking about?
 
Hi, Thanks for the reply.
It is a 850 kWp system. And utility does not mention anything on the protection requirements.
Are there any benchmarks in terms of system size to recommend protection relays in addition to a breaker?
 
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This system is divided into three sections and connected to one of the distribution boards of the production plant as follows.
1. 3 x 100kVA inverter
2. 2 X 100kVA and 1 X 30kVA
3. 1 X 100kVA and 1 X 60kVA

All at 480V.
 
SS_EE said:
This system is divided into three sections and connected to one of the distribution boards of the production plant as follows.
1. 3 x 100kVA inverter
2. 2 X 100kVA and 1 X 30kVA
3. 1 X 100kVA and 1 X 60kVA

All at 480V.
Click to expand...
Again, the only numbers of significance to the interconnection are the total inverter maximum output currents X1.25 for each interconnection. BTW, do the three sections connect to three meters (services) or do they all ultimately feed a single service?
 
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