Flowserve Limitorque Master Station III - Manual (Page 17)

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Limitorque Master Station III FCD LMENIM5001-02 – 12/13
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4.3 Master Station Wiring Requirements
The network cable connects the field units to the host controller or Master Station. Belden 3074F,
3105A, or 9841 shielded, twisted-pair cable should be used. The use of other cables may result in a
reduction of internodal distances or increased error rate, and is the user’s responsibility.
BELDEN 3074F SPECIFICATIONS
• Total cable length between repeaters or nodes with repeaters: up to 19.2 kbps: 4000’(1.2 km)
For loop mode, this is the total length between operating field units. If a field unit loses power, the
relays internal to the field unit connect the A1 Channel to the A2 Channel, which effectively doubles
the length of the cable (assuming a single field unit fails). To ensure operation within specifications
in the event of power failure to field units, this consideration must be added. Example: To ensure
operation within specification when any two consecutive field units lose power, the maximum length
of cable up to 19.2 bkps should not exceed 4000’ (1.2 km) per every four field units.
Key Specifications
• Resistance/1000 ft = 18 AWG (7 x 26) 6.92 ohms each conductor (13.84 ohms for the pair)
• Capacitance/ft = 14 pF (conductor-to-conductor)
• Capacitance/ft = 14 pF (conductor-to-shield)
BELDEN 3105A SPECIFICATIONS
• Total cable length between repeaters or nodes with repeaters: up to 19.2 kbps: 4000’ (1.2 km)
For loop mode, this is the total length between operating field units. If a field unit loses power, the
relays internal to the field unit connect the A1 Channel to the A2 Channel, which effectively doubles
the length of the cable (assuming a single field unit fails). To ensure operation within specifications
in the event of power failure to field units, this consideration must be added. Example: To ensure
operation within specification when any two consecutive field units lose power, the maximum length
of cable up to 19.2 bkps should not exceed 4000’ (1.2 km) per every four field units.
Key Specifications
• Resistance/1000 ft = 22 AWG (7 x 30) 14.7 ohms each conductor (29.4 ohms for the pair)
• Capacitance/ft = 11.0 pF (conductor-to-conductor)
• Capacitance/ft = 20.0 pF (conductor-to-shield)
BELDEN 9841 SPECIFICATIONS
• Total cable length between repeaters or nodes with repeaters: up to 19.2 kbps: 3500’ (1 km)
For loop mode, this is the total length between operating field units. If a field unit loses power, the
relays internal to the field unit connect the A1 Channel to the A2 Channel, which effectively doubles
the length of the cable (assuming a single field unit fails). To ensure operation within specifications
in the event of power failure to field units, this consideration must be added. Example: To ensure
operation within specification when any two consecutive field units lose power, the maximum length
of cable up to 19.2 bkps should not exceed 3500’ (1 km) per every four field units.
Key Specifications
• Resistance/1000 ft = 24 AWG (7 x 32) 24 ohms
each conductor (48 ohms for the pair)
• Capacitance/ft = 12.8 pF
(conductor-to-conductor)
• Capacitance/ft = 23 pF (conductor-to-shield)