4
Precautions
1. Installation precautions
Caution
This instrument is intended to be used under the following environmental conditions
(IEC61010-1): Overvoltage category
, Pollution degree 2
Ensure the mounting location corresponds to the following conditions:
• A minimum of dust, and an absence of corrosive gases
• No flammable, explosive gases
• No mechanical vibrations or shocks
• No exposure to direct sunlight, an ambient temperature of 0 to 50
(32 to 122 ) that does not change
rapidly
• An ambient non-condensing humidity of 35 to 85%RH
• No large capacity electromagnetic switches or cables through which large current is flowing
• No water, oil or chemicals or where the vapors of these substances can come into direct contact with
the unit
Note: Do not install this instrument near flammable material even though the case of this instrument is
made of flame resistant resin.
Avoid setting this instrument directly on flammable material.
2. Wiring precautions
Caution
• Do not leave bits of wire in the instrument, because they could cause fire or malfunction.
• Use the solderless terminal with an insulation sleeve in which the M3 screw fits when wiring the KT4H/B.
• The terminal block of this instrument is designed to be wired from the left side.
The lead wire must be inserted from the left side of the terminal, and fastened with the terminal screw.
• When using a Terminal cover (AKT4H801), pass terminal wires numbered 7 to 12 into the holes of the
terminal cover. See (Fig. 3.4-2) on page 8.
• Tighten the terminal screw to within the specified torque.
If excessive force is applied to the screw when tightening, the terminal screw or case may be damaged.
• This controller does not have a built-in power switch, circuit breaker or fuse. It is necessary to install
them near the controller.
(Recommended fuse: Time-lag fuse, rated voltage 250V AC, rated current 2A)
• For a 24V AC/DC power source, do not confuse polarity when using direct current (DC).
• Do not apply a commercial power source to the sensor which is connected to the input terminal nor
allow the power source to come into contact with the sensor.
• To extend a thermocouple’s lead wire, be sure to use a compensating lead wire in accordance with
the sensor input specification.
(If any other compensating lead wire is used, a temperature indication error may be caused.)
• Use the 3-wire RTD according to the sensor input specifications of this controller.
• (+) side input terminal number of 0 to 5V DC, 1 to 5V DC, 0 to 10V DC differs from that of 0 to 1V DC.
(+) side input terminal number of 0 to 5V DC, 1 to 5V DC, 0 to 10V DC: 9
(+) side input terminal number of 0 to 1V DC: 10
• When using a relay contact output type, use a relay according to the capacity of the load to protect the
built-in relay contact.
• When wiring, keep input wires (thermocouple, RTD, etc.) away from AC sources or load wires to avoid
external interference.
3. Operation and maintenance precautions
Caution
• It is recommended that the PID auto-tuning be performed on the trial run.
• Do not touch live terminals. This may cause electric shock or problems in operation.
• Turn the power supply to the instrument OFF before retightening the terminal and cleaning.
Working on or touching the terminal with the power switched ON may result in severe injury or death
due to Electric Shock.
• Use a soft, dry cloth when cleaning the instrument.
(Alcohol based substances may deface or tarnish the unit.)
• As the display section is vulnerable, do not strike or scratch it with a hard object.
