16
SAPTF33xx-1xx
24-hour Technical Support: 1-800-260-1312 -- International: 00-1-952-941-7600
Operation — Continued
Loop-start operation
Loop-start service (commonly known as “Plain Old Telephone Service” (POTS) is
the primary analog signaling method used between telephone switches such as the
Central Office (CO) and a telephone device. Loop-Start provides a way to indicate
on-hook and off-hook conditions, which facilitates outgoing and incoming calls in a
voice network.
When a customer wants to make an outgoing call, the customer takes a telephone
device off-hook. This action completes the loop, which signals the CO that a
customer desires to use the telephone line. To signal the customer of an incoming
call, the CO applies a ring voltage to alert the customer.
The three states of the Loop-Start signaling protocol are described below:
Idle state (on-hook)
1. The CO applies a battery voltage to the ring lead and monitors the tip-ring
current for closure of the tip-ring.
2. The telephone device draws less than 10 µA of from the line.
Telephone in-use (off-hook)
1. The customer takes the telephone device off-hook, drawing a minimum of
20 mA of current.
2. The CO senses the tip-ring current and issues a dial tone on the line.
3. Communication can now begin.
Central office (CO) rings the telephone
1. The CO places an AC pulse-ringer voltage on top of the -48VDC ring
lead signal.
2. The telephone device uses the AC pulse-ringer voltage to operate the
ringer, which alerts the customer of an incoming telephone call.
3. The customer takes the phone off-hook, which closes the tip-ring
connection and allows the tip-ring current to flow.
4. The CO senses in DC current level and connects the call to the telephone
line.
5. Communication can now begin.
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Cable Specifications
Copper cable—category 1
ISO/IEC 11801; TIA/EIA 568-B Standards
Cable types: Shielded (STP) or unshielded (UTP) twisted-pair is acceptable.
Maximum Cable Length: 5 km (3.1 mi)
Fiber cable
Bit error rate: ≤10-9
Single mode fiber (recommended): 9 µm
Multimode fiber (recommended): 62.5/125 µm
Multimode fiber (optional): 100/140, 85/140, 50/125 µm
SAPTF3311-105, SAPTF3311-115 1300 nm multimode
Fiber Optic Transmitter Power: min: -19.0 dBm max: -12.0 dBm
Fiber Optic Receiver Sensitivity: min: -31.0 dBm max: -8.0 dBm
Link Budget: 12.0 dB
SAPTF3312-105, SAPTF3312-115 1310 nm single mode
Fiber Optic Transmitter Power: min: -15.0 dBm max: -8.0 dBm
Fiber Optic Receiver Sensitivity: min: -32.0 dBm max: -5.0 dBm
Link Budget: 17.0 dB
SAPTF3313-105, SAPTF3313-115 1300 nm multimode
Fiber Optic Transmitter Power: min: -19.0 dBm max: -12.0 dBm
Fiber Optic Receiver Sensitivity: min: -31.0 dBm max: -8.0 dBm
Link Budget: 12.0 dB
SAPTF3314-105, SAPTF3314-115 1310 nm single mode
Fiber Optic Transmitter Power: min: -18.0 dBm max: -7.0 dBm
Fiber Optic Receiver Sensitivity: min: -32.0 dBm max: -3.0 dBm
Link Budget: 14.0 dB
SAPTF3315-105, SAPTF3315-115 1310 nm single mode
Fiber Optic Transmitter Power: min: -27.0 dBm max: -10.0 dBm
Fiber Optic Receiver Sensitivity: min: -34.0 dBm max: -14.0 dBm
Link Budget: 13.0 dB
SAPTF3316-105, SAPTF3316-115 1310 nm single mode
Fiber Optic Transmitter Power: min: -5.0 dBm max: 0.0 dBm
Fiber Optic Receiver Sensitivity: min: -38.0 dBm max: -7.0 dBm
Link Budget: 33.0 dB
SAPTF3317-105, SAPTF3317-115 1550 nm single mode
Fiber Optic Transmitter Power: min: -5.0 dBm max: 0.0 dBm
Fiber Optic Receiver Sensitivity: min: -34.0 dBm max: -3.0 dBm
Link Budget: 29.0 dB
