Edwards Signaling 128C GuardSwitch User Manual
128c, Guardswitch, Series 100
www.ge-security.com/industrial
128C-2N-06(J)
128C-GN-06(J)
128C-GN-12(J)
128C-6N-06(J)
128C-6N-12(J)
128C
Installation
1. Using the following guidelines, determine a suitable mounting location:
• The switch and actuator must be within the listed sense range. See Ordering/
Electrical Specifications.
• The sense ranges are based on switch and actuator aligned so the sensing
surfaces are face to face. (See figure 1.)
Important: When mounting in proximity to ferrous material (steel), the sense
range can be reduced 50% minimum depending on the shape and type of
material. Test the switch in specific applications to determine the actual
sense range.
• When mounting on a ferrous material (steel), a 1/4" nonferrous (plastic or
aluminum) spacer may be used around the actuator and switch to restore most
of the lost gap.
• When mounting on a hinged gate or door, mount the switch and actuator at least
6" away from the hinges to achieve the maximum movement.
• The switch and actuator must move in one of the approved directions.
See Figure 1.
• The actuator can be mounted at a 90
°
rotation to the switch.
• Do not mount for parallel actuation. An on-off-on signal may result when the
actuator passes by the switch.
2. Mount the switch on the stationary frame of the machine and connect the electrical
wiring. When mounting the switch on an ungrounded machine, connect the ground
lead to one of the mounting screws.
3. Mount the actuator on the movable guard, door, or gate.
continued
Warning! To avoid switch failure determine the actual load of the switch circuit and
take steps to protect the switch from voltage spikes, current inrush and line/load
capacitance using the following recommendations.
• Surges from coils, motors, contactors, solenoids and tungsten filaments. Transient
protection, such as back-to-back zener diodes (Transorb) or an RC network, is
recommended for such loads to ensure that maximum ratings of the switch are
not exceeded.
• Line capacitance and load capacitance. An in-line resistor can be added in series
immediately before the load to limit the inrush current. The resistor can only be
added in series with the last wire just before the load. The voltage drop and the
power rating of the resistor must also be calculated as follows:
Voltage drop = I • R
Watts = I
2
• R
( I = maximum continuous current of the load)
To verify switch operation with an ohmmeter:
Set range at 20 mega ohms (switches with triac output, set ohm range at 20 kilo
ohms). For a normally open switch, the meter will read a high impedance with the
actuator away. It will read very high to infinity range (triac switches will read high kilo
ohm to infinity range) with the actuator within sense range. You will see the opposite
reading for a normally closed switch.
Figure 1
Non-Contact Interlock/Position Switch
Dimensions
128C-9N-06(J)
128C-9N-12(J)
128C-_________
Actuator______
Figure 2
Barrel Switch Mounting Configurations
End-to-End
Side-by-Side
OK
OK
NO
Perpendicular
OK
Three configurations are appropriate for recessed interlock applications. Moving the
actuator parallel to the switch can result in on/off/on signal if the actuator passes by
the switch rather than coming to rest in proximity to it. This is NOT a recommended
configuration for interlock/position applications. The "T" configuration results
in non-actuation.
“T”
1.97''
5.0cm
0.32''
0.81cm
0.15''
0.38cm
M8 x 1.25
0.57''
1.45cm
0.50''
1.27cm
Switch
Actuator
sensing
faces
GuardSwitch
™
Series 100