Dulas VC150SDD, Installation & Technician'S Manual

Page: 33 / 47

VC150SDD Installation & Technician’s Manual
Page 33 of 47
25. Troubleshooting Guide
Section 1 General description
The VC150SDD is based on well proven technology and components and should prove to be very
reliable in operation. However if there is a fault it has been designed for easy access to the main
components. Please refer to the pictures in Section 4 for a guide to the various components.
Description of components on the wiring diagram
(Refer to section 27. VC150SDD Electrical Schematic)
All wires lead to the SDD control board, so power from the PV flows through the control to the
compressor, capacitor etc.
The capacitor provides a short term energy store to keep the compressor running during brief
reductions in light intensity. It’s also required for starting of the compressor. There is a “bleed”
resistor connected in parallel with the capacitor to ensure that it discharges when the PV is
disconnected. However this takes some time: wait one minute after power has been removed.
The switch / circuit breaker marked on FU1 the diagram provides over current protection and PV
isolation. It should always be turned off during connection and disconnection of the PV array, and
whilst working on the circuit wiring.
The Dulas Lightning Protection Board is intended to protect the refrigerator from high voltages
caused by lightning strikes. It is not a substitute for proper earthing of the PV module frames.