Net Safety MAN-0069, Руководство пользователя

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Net Safety Monitoring Inc
Modbus Controller & 4-20 Fire Head 3
STEP 3 — W
IRE
F
IELD
I
NSTALLATION
WARNING:
Wiring codes and regulations may vary. Compliance with regulations is the
responsibility of the installer. Wiring must comply with applicable regulations
relating to the installation of electrical equipment in a hazardous area. If in
doubt, consult a qualified official before wiring the system.
• If the 4-20 mA output signal is not used, connect a jumper between the 4-20
terminal and the Common terminal.
• The use of shielded cable is highly recommended for signal, input, output and
power wires to protect against interference caused by extraneous electrical or
electromagnetic 'noise'.
• In applications where the wiring cable is installed in conduit, the conduit
must not be used for wiring to other electrical equipment.
• The maximum distance between the Sensor and Controller is limited by the
resistance of the connecting wiring, which is a function of the gauge of the
wire being used.
• When developing a RS-485 chain of devices, the last device in the chain
requires end of line termination.
• RS-485 connection 2-wire, multipoint serial line.
S
EAL
• Water-proof and explosion-proof conduit seals are recommended to prevent
water accumulation within the enclosure.
• Seals should be located as close to the device as possible and not more than
18 inches (46 cm) away.
• Explosion-proof installations may require an additional seal where conduit
enters a non-hazardous area. Ensure conformity with local wiring codes.
• When pouring a seal, use a fibre dam to assure proper formation of the seal.
Seals should never be poured at temperatures below freezing.
• The jacket and shielding of the cable should be stripped back to permit the
seal to form around the individual wires. This will prevent air, gas and water
leakage through the inside of the shield and into the enclosure.
• It is recommended that explosion-proof drains and conduit breathers be used.
In some applications, alternate changes in temperature and barometric
pressure can cause 'breathing' which allows moist air to enter and circulate
inside the conduit. Joints in the conduit system are seldom tight enough to
prevent this 'breathing'.
Connecting Wires
1. Use a small screw driver to gently press down
and hold the spring connector open.
2. Insert appropriate wire into open connector
hole.
3. Release screw driver to secure wire.
Figure 3: Internal PCB Boards
Option Board/RS-485 Modbus RTU
Communication Board
(refer to Figure 4 for
details).
Sensor Board
(refer to Figure 4 for
details).
Terminal Board
(refer to Figure 4 for
details).