Applications

 Telephone lines

 DSL Lines

 T1/E1/J1 lines

 Balanced audio lines

Features

 Protection for up to four pairs of lines

 Three-Stage protection

 Superior to diode or TVS only based designs

 Weatherproof ABS enclosure

 Removable screw terminal blocks

Description

The AL-D4-DTW is a high performance 3-stage weatherproof protector that provides superior protection of

differential or balanced digital or analog lines from transients and surges. This unit will protect up to four pairs of

differential data or analog signal/control lines.

The first stage is comprised of a differential gas discharge tube. Stage two is a pair of current limiting series

resistors and the final stage is a low capacitance diode array. The second stage series resistance limits the power

dissipation of the fast diode clamp array in the third stage. This allows time for the slower but higher power gas

tubes to flash over. The diode array clamps the leading edge of fast transients to safe levels until the high power

gas tubes turn on. This eliminates the damaging leading edge spike that single stage gas tube protectors let leak

through. The diode array’s low capacitance assures that the suppressor will not degrade the high-speed signals.

The 3-stage design can handle higher-level transients than a protector that

uses only diodes. The design utilizes Thyristor diode technology which has

superior power handling capability compared to TVS or Avalanche diode based

designs.

Failsafe Feature

The AL-D4-DTW series is designed to convert into a failsafe mode in the rare

case of a catastrophic surge or lightning event. For this mode, the resistors in

the second stage will fuse and portions of the diode array will short. This

effectively disconnects the line from sensitive equipment thus limiting damage.

The units are factory repairable.