User's Manual

6-2 Errors and Remedies
6-2
6-3
The following are considered to be main causes of system breakdowns.
• Noise Interference.......................................Take appropriate countermeasures against noise.
• Failures in any of the external devices
• Failures in the Reader/Writer
• Failures in the Antenna
• Failures in the cable
• Failures in any of the Tags
• Others
■ Noise Interference
If the system malfunctions due to noise, refer to the following and take appropriate
countermeasures.
No. Circumstance of
failure
Probably cause Remedy
1
An instantaneous voltage drop due
to inrush current to the heavy load.
Increase the capacity of the power supply and
that of the power cable.
Occurs when a
heavy-duty motor,
transformer, or
capacitor is turned ON.
Common mode noise caused by the
above cause.
Provide the power througha 1-to1non-grounded
insulating transformer.
Independently ground the Reader/Writer at a
resistance less than 100 ohm.
2 Occurs irregularly
Noise on power line Provide the power through a 1-to-1
non-grounded insulating transformer or noise
filter.
Independently ground the Reader/Writer at a
resistance less than 100 ohm.
Noise propagated through space
1. When a power circuit, power
wire, or other signal wires for the
devices are located near the
antenna.
2. When a driving system such as
an inverter or motor is located
nearby.
3. When a power unit such as a
switching power source is located
nearby.
1. Place the power circuit, power wire, or other
signal wires for the devices as far away from the
antenna as possible.
Be sure to wire antenna cables separately from
other cables. Shield the power circuit, power
wire, or signal wires for other devices.
2. Be sure to ground the unit of the driving
system. Place the unit as far away from the
antenna as possible.
3. Be sure to ground the power unit. Place the
unit as far away from the antenna as possible.
More than one V720-series
Antenna
When operating more than one V720-series
Antenna, provide a sufficient clearance between
the Antennas.
Refer to the instruction manual for your
antenna for details.
Improvement of grounding Remedy for power noise
Repairs are requi red.
Other
equipmen
Reader/Writer
Reader/Writer
Other
equipment
Reader/Writer
Use twisted - pair wires.
Do not install them in parallel
with other power lines.
Line filter
+24 V DC
0 V
connecting to
a ground of
100 ohm or less