Rectifying incorrect terminations – 22kW existing system

Maintenance

NWT were invited to tender for a 70kW solar PV by one of the UK’s leading property agents. The site already had two independent solar PV systems in place already, rated at 98kW and 22kW, which had been installed previously. NWT were successful in the tender process and, following the instruction to proceed with the installation of the new system, were also asked to inspect the existing systems in order to check for any issues and to ensure that they were operating effectively. Following the inspection there were a number of issues to address.

Rectifying incorrect terminations – 22kW existing system

22kW System

 

PV string issue

One string, an estimated 24 panels (approximately a third of the total), that was part of the 22kW array was not producing any power. The DC cables from the arrays had not been terminated in to the ‘Sunclix’ inverter plugs correctly, meaning that there was overheating of the connection during times of high production. One of the plugs had failed as a result of this and needed to be replaced.

TerminationHorton Park Term

 

 

 

 

 

 

 

 

 

It appeared by the tarnished appearance of the conductors at the point of failure that this string has been out of action for some considerable time.

 

 Out-dated Firmware

In addition to this NWT identified that the inverter firmware was out of date and as such that the inverter efficiency could be improved by updating to a newer version.

The remaining existing plugs also needed to be terminated correctly to negate the risk of any more plugs overheating. This work had the added benefit of reducing system losses slightly.

All of this remedial work was corrected at a low cost which, given the FIT rate that the system was registered on, will pay for itself in a matter of months and continue to increase revenues from then on.