SIDAC
TELECOMMUNICATION SYSTEM PROTECTORS
C3100D50, C3100D75, C3100D100
Product Description
These devices are designed to limit overvoltages on the telephone line. Overvoltages
are normally caused a.c. power system or lightning flash disturbances which are induced
or conducted on to the telephone line. A single device provides 2-point protection and is
typically used for the protection of 2-wire telecommunication equipment (e.g. between
the Ring and Tip wires for telephones and modems). Combinations of devices can be
used for multi-point protection (e.g. 3-point protection between Ring, Tip and Ground).
The protector consists of a symmetrical voltage-triggered bi-directional thyristor.
Overvoltages are initially clipped by breakdown clamping until the voltage rises to the
breakover level, which causes the devices to crowbar into a low-voltage on state. This
low-voltage on state causes the current resulting from the overvoltage to be safely
diverted through the device. The high crowbar holding current prevents d.c. latchup as
the diverted current subsides. These protectors are guaranteed to voltage limit and
withstand the listed lightning surges in both polarities.
Advantages
The advantages of using this device over other surge suppression devices is that the
device offers absolute surge protection regardless of the surge current available and the
rate of applied voltage (dV/dt). Unlike other devices, the device:
‧ Can not be damaged by voltage
‧ Eliminates hysteresis and heat dissipation typically found with a clamping
device
‧ Eliminates voltage overshoot caused by fast rising transients
‧ Is non-degenerative
‧ Will not fatigue
‧ Has negligible capacitance making it ideal for high speed transmission
equipment
Applications
‧ Customer Premises Equipment (CPE) such as phone, modems and caller ID
adjunct boxes
‧ T-1/E-1, ISDN and xDSL transmission equipment
‧ Data lines and security systems
‧ Primary protection including main distribution frames, building entrance
equipment and station protection modules
Version 1.0
1/4
1 April 2001
CERAMATE [ CERAMATE TECHNICAL ]
