Banner EZ-SCREEN­ Safety Light Curtain Systems - Manual (Page 48)

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P/N 68413 rev. A
Banner Engineering Corp. • Minneapolis, U.S.A.
www.bannerengineering.com • Tel: 763.544.3164
EZ-SCREEN Point
Instruction Manual
Troubleshooting and Maintenance
5.2 Electrical and Optical Noise
The EZ-SCREEN System is designed and manufactured to be
highly resistant to electrical and optical noise and to operate
reliably in industrial settings. However, serious electrical and/or
optical noise may cause a random trip or latch condition. In very
extreme electrical noise cases, a lockout is possible. In order
to minimize the effects of transitory noise, the EZ-SCREEN
System will respond to noise only if the noise is detected on
multiple consecutive scans.
If random nuisance trips occur, check the following:
• Poor connection between the sensor and earth ground;
• Optical interference from adjacent light grids or other
photoelectrics; or
• Sensor input or output wires routed too close to “noisy”
wiring.
Checking for sources of electrical noise: It is very important
that the EZ-SCREEN Point sensors have a good earth ground.
Without this, the system can act like an antenna and random
trips and lockouts can occur .
All EZ-SCREEN System wiring is low voltage; running these
wires alongside power wires, motor/servo wires, or other high-
voltage wiring, can inject noise into the EZ-SCREEN system. It
is good wiring practice (and may be required by code) to isolate
EZ-SCREEN System wires from high-voltage wires.
The Banner BT-1 Beam Tracker is a very good tool for detecting
electrical noise . It can be used to detect electrical transient
spikes and surges. Cover the lens of the BT-1 with electrical
tape to block optical light from getting into the receiver lens.
Press the “RCV” button on the BT-1 and position the Beam
Tracker on the wires going to the EZ-SCREEN or any other
nearby wires. Noise caused by the switching of inductive loads
should be addressed by installing proper transient suppression
across the load .
Checking for sources of optical noise: Turn off the emitter,
completely block the emitter beam, or open the Test input,
then use a Banner BT-1 Beam Tracker to check for light at
the receiver. Press the “RCV” button on the BT-1 and move it
across the full length of the receiver’s sensing window. If the
BT-1’s indicator lights, check for light from other sources (other
safety light screens, grids or points, or standard photoelectric
sensors) by “tracking down” the emitted light from them.
WARNING . . .
Shut Down
Machinery before Servicing
The machinery connected to the EZ-SCREEN
System must not be operating at any time during this
procedure. Some servicing procedures may involve working close
to the hazardous areas of the guarded machine .
Serious bodily injury or death could result.
CAUTION . . .
Electrical Danger
Exercise care whenever troubleshooting,
repairing, or modifying the EZ-SCREEN System
and/or the machine control system. Always disconnect all
power from the EZ-SCREEN System and the guarded machine
before making any wire connections or before replacing any
component.
Electrical connections or repairs should be done only by a
Qualified Person (see Safety Glossary).
WARNING . . .
Power Failures and
Lockouts
A lockout is a definite indication of a problem
and should be investigated at once, by a Qualified Person.
Attempts to continue to operate machinery by bypassing the
EZ-SCREEN System are dangerous and could result in serious
bodily injury or death.