Suggested Specification - Transient Voltage and Surge Suppression Devices

Protection against surge currents and electrical noise for the whole installation is to be achieved in a 2 stage approach.

The first diversion shall be at the main switchboard on each incoming supply. Then any residual voltage resulting from the action (of the suppression device) can be dealt with by a second protective device at the distribution boards with critical loads.

Each TVSS device shall have 7 modes of protection and have directly connected suppression elements between line - neutral (L-N), line - ground (L-G) and neutral - ground (N-G).

Each unit shall incorporate a high performance EMI/RFI noise rejection filter. Noise attenuation shall be 55dB at 100kHz using the MIL-STD-220A insertion loss test method (40dB for distribution boards).

Safety and diagnostic monitoring shall be provided in each unit as listed below:

• Continuous monitoring of 200kAIC internal fuses.
• Internal infrared sensor system for monitoring MOVs.
• A thermal detection circuit shall monitor for overheating in all modes due to thermal runaway.
• Remote status (changeover contacts) shall be provided.
• Green/red indicator lights shall be provided on each phase, absence of green light and presence of red shall indicate which phase(s) have been damaged.

A) Main Switchboard TVSS Devices.
Shall be mounted in the main switchboard(s) as close as practical to main incoming bus bars (not more than 30cm) supplied via a 32A circuit breaker and have the additional features listed below. The device shall be a TYCOR model PTY-S2-480Y/277-SD or approved equivalent.

• 160kA surge current per phase.
• Matched MOV array.
• UL 1449 and UL 1283 listed, CSA 22.2 Certified.
• Repetitive Withstand Testing ANSI/IEEE C3, 2,500 surges.

B) Distribution Board(s) TVSS Device.
Shall be mounted in the distribution board(s) as indicated on the drawings, as close as practical to the incoming bus bar system, supplied by a 32A circuit breaker and have the additional features listed below. The device shall be a TYCOR model PTY-B-480Y/277-SD or approved equivalent.

• 90kA surge current per phase.
• Matched MOV array.
• UL 1449 and UL 1283 listed, CSA 22.2 Certified
• Repetitive Withstand Testing ANSI/IEEE C3, 1500 surges.

C) Critical Final Sub-Circuits.
Where indicated on the drawings for critical circuits such as micro processors, PLCs robotics machines, electronic apparatus install a TYCOR model AEGIS series connected AC powerline filter or approved equivalent.

The filter is to be mounted within the associated distribution board and have it's rating (3,5,10 or15A) determined by the circuit load current.

Click here for how to install TVSS