Cautions On Connections - Omega RD2800 Series User Manual

4. CONNECTIONS 4.2
Observe the following cautions during connections for securing safety and reliability.
Power supply
1
Use a single-phase power supply having a stable
voltage without any waveform distortion for the
purpose of preventing wrong operations.
A switch and an overcurrent
Warning
protective device
Prepare a switch and an overcurrent
protective device (3 A) to the power
supply for preventing
electric shock during connection work.
This instrument is not provided with any
replaceable overcurrent protective device.
Turn off the power supply
Warning
before starting connections.
Make sure to turn off the power supply
before connecting the power and the
input/output terminals to prevent an
electric shock.
2 Keep the input/output connections
away from high voltage power
circuits
Don't place the input/output cables close to or in
parallel with any strong power circuits including
power lines. Place the cables 50cm or more away
from high voltage power circuits when they are
placed close to or in parallel to other circuits.
3 Keep the thermocouple input away
from a heat source
For thermocouple inputs, keep the input terminals
away from a heat source (a heating body) to
reduce a reference junction compensation error.
Don't expose the input terminals to direct sunlight,
etc.
Kinds of terminals and termination
Reference
Screw
Terminal block
diameter
Power and
protective
conductor
terminals
Terminals other
than described M3.5
above

Cautions on Connections

an accidental
Tightening
torque
M4
1.2N • m
8 or less 3.7 or more
0.8N • m
*Use Type O chip (on the left) whenever possible.
－１４－
4 Keep the input/output connections
away from noise source
Keep all connection cables away from noise
source as far as possible, otherwise a malfunction
may occur. Provide a solution if the cables cannot
be separated from a noise source due to
unavoidable circumstances.
Major noise sources
Electromagnetic switch,
etc. Power line having
waveform distortion,
Inverter, Thyristor regulator
5 Use crimp style terminals
(1) Mount crimp style terminals for connection
cable terminations to prevent any looseness
or disconnection of terminals or a short-circuit
failure between terminals.
(2) Use the crimp style terminals with an
insulation sleeve to prevent an electric
shocks.
6 Unused terminals
Don't use any unused terminals for relaying,
otherwise the electric circuits may be damaged.
Secure the connected
Warning
cables properly.
Secure the connected cables so as not to
allow them to be hooked by a person or a
substance, otherwise the connections may
be cut and disrupted, and may cause an
electric shock or other accidents.
Termination (unit: mm)
t : 0.8, with an insulation sleeve
8.5 or less 4.3 or more
(with an insulation sleeve)
8 or less
t : 0.8, with an insulation sleeve
Remedial measures
Insert noise filters
between power
terminals and
input/output terminals.
A CR filter is often used.
3.7 or more