OCTOBER 2000 - REVISED JULY 2008

Specifications are subject to change without notice.

Customers should verify actual device performance in their specific applications.

GR-1089-CORE, “1089”, covers electromagnetic compatibility and electrical safety generic criteria for US network telecommunication

equipment. It is a module in Volume 3 of LSSGR (LATA (Local Access Transport Area) Switching Systems Generic Requirements,

FR-NWT-000064). In ‘1089, surge and power fault immunity tests are done at two levels. After first-level testing, the equipment shall not be

damaged and shall continue to operate correctly. Under second-level testing, the equipment shall not become a safety hazard. The equipment

is permitted to fail as a result of second-level testing. When the equipment is to be located on customer premises, second-level testing

includes a wiring simulator test, which requires the equipment to reduce the power fault current below certain values.

The following clauses reference the ‘1089 section and calculate the protector stress levels. The TISP61089B needs a 40 Ω series resistor to

survive second-level surge testing. To survive first-level testing and possibly fail under second-level testing allows lower resistor value of 25 Ω

to be used. Tabulated current values are given for both 40 Ω and 25 Ω series resistor values.

Figure 12 shows a typical TISP61089B SLIC card protection circuit. The incoming line conductors, Ring (R) and Tip (T), connect to the relay

matrix via the series overcurrent protection. Fusible resistors, fuses and positive temperature coefficient (PTC) resistors can be used for

overcurrent protection. Resistors will reduce the prospective current from the surge generator for both the TISP61089B and the ring/test

protector. The TISP7xxxF3 protector has the same protection voltage for any terminal pair. This protector is used when the ring generator

configuration may be ground or battery-backed. For dedicated ground-backed ringing generators, the TISP3xxxF3 gives better protection as

its inter-conductor protection voltage is twice the conductor to ground value.

Relay contacts 3a and 3b connect the line conductors to the SLIC via the TISP61089B protector. The protector gate reference voltage comes

TISP61089B High Voltage Ringing SLIC Protector

Application Circuit

LSSGR 1089

‘1089 Section 4.5.5 - Test Generators

The generic form of test generator is shown in Figure 13. It emphasises that multiple outputs must be independent, i.e. the loading condition of

one output must not affect the waveforms of the other outputs. It is a requirement that the open-circuit voltage and short circuit current

waveforms be recorded for each generator output used for testing. The fictive impedance of a generator output is defined as the peak open-

circuit voltage divided by the peak short-circuit current. Specified impulse waveshapes are maximum rise and minimum decay times. Thus, the

10/1000 waveshape should be interpreted as <10/>1000 and not the usually defined nominal values which have a tolerance.

Figure 13. ‘1089 Test Generators

or

Generic Lightning or AC Test Generator

Z is the fictive

current-limiting

impedance in

each output feed

Z

Z

Output 1

Output 2

Return

Z

Z

Output n

Output n + 1

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