Hach Accu4 User Manual page 9

Electrical installation
W A R N I N G
Potential electrocution hazard. In order to maintain the NEMA/IP
environmental ratings of the enclosure, use only conduit fittings and
cable glands rated for at least NEMA 4X/IP66 to route cables in to the
instrument.
W A R N I N G
Potential Electrocution Hazard. Always disconnect power to the
instrument when making electrical connections.
• Put all wiring to the sensor and controller in ½-inch, grounded metal
conduit to protect the cable from moisture, electrical noise or
mechanical damage.
If only shielded cables are used, applicable strain reliefs or cable grips
are necessary. Accessory watertight cable grips (3H1091) and
locknuts (3H1230) are available from the manufacturer.
• Make sure that the diameter of the cables used is 4.3–11.4 mm (0.17–
0.45 in.) so that the cable strain reliefs hold the cables securely when
tightened.
• Do not put more than one cable in a cable strain relief.
• Close all unused cable entry holes with applicable plugs to keep out
moisture.
• Close all unused cable strain reliefs with rods or cables to keep out
moisture.
Electrostatic discharge (ESD) considerations
N O T I C E
Potential Instrument Damage. Delicate internal electronic components
can be damaged by static electricity, resulting in degraded
performance or eventual failure.
Refer to the steps in this procedure to prevent ESD damage to the
instrument:
• Touch an earth-grounded metal surface such as the chassis of an
instrument, a metal conduit or pipe to discharge static electricity from
the body.
• Avoid excessive movement. Transport static-sensitive components in
anti-static containers or packages.
• Wear a wrist strap connected by a wire to earth ground.
• Work in a static-safe area with anti-static floor pads and work bench
pads.
Wiring overview
Figure 5 shows the wiring connections and fuses for the controller.
English 9