The surge protector element for each line consists of:
•
Heavy-duty, (2) element gas tube
•
External backup gap assembly
•
Unique switch grade shorting mechanism
Telephone Line Gas Discharge Lightning Surge Protector Specifications
CWT Part number
640-6500
Description
Sealed gas tube station protector
DC Breakdown@100V/s
300-500V
Impulse Breakdown
100V/µs
10kV/µs
100V/µs, vented
600V
850V
1200V
Insulation Resistance@100V/leakage current
10e10
Ω
Capacitance@1kHz <15pF
DC Extinguishing (Network applied) @52V, 135V, 150V
<150ms
Impulse Life Characteristics
>400x500A 10/1000µs
10kA 8/20µs
AC Life characteristics
>65A, 11 cycles
Enclosure Material
Weather and UV resistant , high impact, flame retardant plastic.
Dimensions
5.7”H x 3.4”W x 2.2”D
Table 10: Telephone Line Surge Protector
5
Test & Maintenance
5.1 Diagnostics
5.1.1 Trailblazer Operation
When the Trailblazer is first turned on, the microprocessor boots up and loads the FPGA
and sets the radio parameters. The base unit begins transmitting while the CPE (or
slave unit in an LL system) waits to receive a signal from the base. When the CPE
receives a signal it checks to ensure that the SFD code matches its own SFD code. If
the codes match, the CPE begins adjusting its oscillator frequency to exactly match the
frequency of the base (if the oscillator later drifts due to temperature changes, the CPE
will relock without affecting the link.) Once the CPE oscillator is locked, it transmits a
short ranging packet back to the base. The base unit measures the delay in the return
packet and calculates the approximate path length and sends a correction to the CPE.
The CPE adjusts its timing and sends another short timing packet to the base. This
process continues until the CPE data is arriving in its exact receive window. Then the
CPE begins transmitting full data packets to the base and the link is fully functional. The
base can support up to four CPEs and they are locked and ranged into their appropriate
time slots as they come on line. If a link is broken, the CPE will reset and begin the
process again. If the CPE does not see a signal from the base, it will reset periodically
but will not transmit until it receives permission from the base.
Trailblazer Installation and User Manual
37
