Transient Discriminating Surge Diverter 50 kA AU Three Mode

To meet the fundamental requirements of performance, longer service life and greater safety under real world conditions, ERICO has developed Transient Discriminating (TD) technology. This quantum leap in technology adds a level of “intelligence to the Surge Protection Device enabling it to discriminate between sustained abnormal over-voltage conditions and true transient or surge events. Not only does this ensure safe operation under practical application, but it also prolongs the life of the protector since permanent disconnects are not required as a means of achieving internal over-voltage protection.

The Core of TD technology:The secret to ERICOs Transient Discriminating Technology is its active frequency discrimination circuit. This patented device can discriminate between a temporary over-voltage (TOV) condition and a very fast transient, which is associated with lightning or switching-induced surges. When the transient frequencies are detected, the patented QuickSwitchTM within TD activates to allow the robust protection to limit the incoming transient. The frequency discriminating circuit that controls the Quick-SwitchTM ensures that the SPD device is immune to the effects of a sustained 50 or 60Hz TOV. This allows the device to keep operating, providing safe and reliable transient protection, even after an abnormal over-voltage condition has occurred.


  • Compact design fits into most distribution panels and motor control centres.
  • Three modes of protection: L-N, L-PE and N-PE.
  • LED status indication and opto-isolated output for remote status monitoring.
  • Optional dry alarm contacts using DINLINE Alarm Relay.
  • Transient Discriminating (TD) technology helps ensure safe operation during abnormal over-voltage events.


Part Number TDS50240
Article Number 700305
Nominal System Voltage (Un) 240 VAC
Max Continuous Operating Voltage (Uc) 340 VAC
Voltage Protection Rating (VPR) 800.0 V @ 3 kA
Max Discharge Current (Imax) 20 kA 8/20 μs L-N
20 kA 8/20 μs L-PE
10 kA 8/20 μs N-PE
Frequency 50 – 60 Hz
Protection Modes L-N
Connection, Stranded 6 mm² Max
Response Time 5 ns Max
Mounting 35 mm top hat DIN rail
Enclosure Material UL® 94V-0 Thermoplastic
Enclosure Rating IP 20
Status Indication LED
Remote Contacts No
Module Width 2 M
Depth (D) 68 mm
Height (H) 90 mm
Width (W) 35 mm
Unit Weight 0.18 kg
Designed to Meet ANSI®/IEEE® C62.41.2 Cat A, Cat B, Cat C
Standard Packaging Quantity 1 pc
UPC 78285644043
EAN-13 8711893029840