Edwards Signaling 171 Series - Manual

www.edwardssignaling.com
171-6Z
171-7Z
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.
Non-Contact Interlock/Position Switch
171
Installation
Use non-removable screws, bolts, or nuts to mount the switch and actuator. Do not
over-torque mounting hardware.
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 actuator must be aligned with the switch—labels facing the same direction.
(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 under 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 2.
• 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.
Dimensions
5.75''
14.61cm
5.27''
13.39cm
0.24''
0.61cm
0.83''
2.11cm
0.42''
1.07cm
5.75''
14.61cm
5.26''
13.36cm
0.24''
0.61cm 0.64''
1.63cm
2.03''
5.16cm
0.64''
1.63cm
2.33''
5.92cm
1.10''
2.79cm
0.28''
0.71cm
1.12''
2.84cm
1.49''
3.78cm
0.22''
0.56cm
dia.
1.51''
3.84cm
Actuator
Switch
conduit
sensing face
sensing face
Figure 1
171-8Z
171-M10
171-_________
GuardSwitch ™ Series 100