Veeder-Root TLS-50 Series, Руководство пользователя

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Site Considerations National Electrical Code Compliance
4
National Electrical Code Compliance
The following information is for general reference and is not intended to replace recommended National Electric
Code (NEC) procedures. It is important for the installer to understand that electrical equipment and wiring located
in Class I, Division 1 and 2 installations shall comply with the latest appropriate articles found in the National
Electric Code (NFPA 70) and the Automotive and Marine Service Station Code (NFPA 30A), or other local code
such as the CEC, Canadian Electrical Code.
PROBE-TO-CONSOLE WIRING
Shielded Cable or Veeder-Root Direct Burial Cable Required
To ensure the best operating systems available, Veeder-Root REQUIRES the use of shielded cable for all probes
regardless of conduit material or application. In these installations, shielded cable must be rated less than 100 pF/
foot (100 pF/304 mm) and be manufactured with a material suitable for the environment, such as Carol
™
C2534
or Belden
™
88760, 8760, or 8770.
Note: Throughout this manual, when mentioning any cable being used for probe-to-console wiring, it will be
referring to shielded cable.
Wire Length
Improper system operation could result in undetected potential environmental and health hazards if the probe-to-
console wire runs exceed 1000 feet (304 m). Wire runs must be less than 1000 feet to meet intrinsic safety
requirements.
Splices
Veeder-Root recommends that no splices be made in the wire run between a probe junction box and the console.
Each splice degrades signal strength and could result in poor system performance.
Wire Gauges - Color coded
•
Shielded cable must be used in all installations. Probe-to-console wires should be #14 - #18 AWG (2.5 to 0.8
mm
2
) stranded copper wire and installed as a Class 1 circuit. As an alternate method when approved by the
local authority having jurisdiction, #22 AWG (>0.3 mm
2
) wires such as Belden 88761 may be suitable in
installations with the following provisions:
- Wire run is less than 750 feet (228 m)
- Capacitance does not exceed 100 pF/foot (100 pF/304 mm)
- Inductance does not exceed 0.2
μ
H/foot (0.2
μ
H/304 mm)
•
Total cable length per installation: 22,000 feet (6700 m).
POWER WIRING
Wires carrying 120 or 240 Vac from the power panel to the console should be #14 AWG (2.5 mm
2
) copper wire
for line, neutral and chassis ground (3); and #12 AWG (4 mm
2
) copper wire for barrier ground (1).
PROBE JUNCTION BOXES
Weatherproof electrical junction boxes with a gasketed cover are required on the end of each probe conduit run at
the manhole location. Gasketing or sealing compound must be used at each entry to the junction box to ensure a
waterproof junction. The interior volume of each junction box must be a minimum of 16 cubic inches (262 cm
3
).
Veeder-Root recommends the following junction box or equivalent:
•
Appleton Electric Co. - JBDX junction box, JBK-B cover, and JB-GK-V gasket.
•
Crouse-Hinds Co. - GRFX-139 junction box, GRF-10 cover, and GASK-643 gasket.