Tadiran Telecom Coral IPx Office, Installation And Hardware Reference Manual, Page: 152 / 510

5-14
External Connections Coral IPx Office Installation Manual
Pr
otection Devices
5
Primary protection absorbs the major impact of infrequent, but dangerous,
catastrophic surges, while secondary protection suppresses constantly occurring
impulses. These impulses, while not dangerous, can cripple valuable, and in many
cases, essential, communication facilities.
Generally, leased or switched circuit facilities provided by the local telephone utility
company are equipped with primary protection devices installed with the circuit.
However, privately owned aerial or buried cable feeding from one building to another
might not be equipped with protection devices. Always consult with whoever
provided the circuits to determine whether protection devices are present, and if so,
what type. Never assume that protection devices have been provided by another party,
or that existing protection devices are adequate.
The secondary protection must include a leakage current protector in series with every
wire, tip and ring, on every port that is either connected to the public telephone
network, or to any cable located outdoors. The requirement is in accordance with UL®
Specification 60950, Third Edition or CSA C22.2 No. 60950. The required protectors
can be mounted directly on a Block 66 in the MDF.
Table 5-4 Telephone
Circuit Primary
Protection Device
Specifications
Specification Measurement
Construction
Primary Element
Fail-safe Metallic Shunt
Vent Safe Spark Gap
Heat Coil (recommended) 3 Electrode Gas Tube
1.0
Ω
to Ground Max.
Per UL 497
1.0A 100 Sec. Max.
Clamp Points (per REA PE-80)
DC.
2kV/S.
100V/
µ
S
10kV/
µ
S
Vent Safe @ 100V/
µ
S
350VDC Max.
400VDC Max.
500VDC Max.
800VDC Max.
1600VDC Max.
DC Impulse Current (8x20
µ
S wave) 10KA Nom.
AC Discharge Current (60Hz/1S) 10A Nom.
DC Holdover (per IEEE 465.1) 160VDC Max.