Surge protection is required for SWIFT 8920 systems if the optional Power Line Conditioner is not purchased. The customer is responsible for installing surge protection at the branch panel to protect the system from transient over-voltages and surges on the mains line due to brief power outages, switching of nearby equipment, etc. Installation of the surge protection is visually verified during the pre-install site survey.The operating voltage of the surge protector is the same as the branch panel voltage (208/230/440). All connections should be in parallel with the branch power lines (L1, L2, L3, ground, and neutral if provided.) Contact the surge protection manufacturer for approval if modification of the wire length is needed for the installation. Contact KLA-Tencor for assistance if needed.