Edwards Signaling 301-BT Series - Manual

© 2013 UTC Fire & Security. All rights reserved. 1 / 6 P/N 13924 • REV D • REB 27FEB13
GuardSwitch Series 300
Switches 301-BT and 303-BT Installation Sheet
Description
The 301-BT Series 300 DPST safety interlock switch is
designed for use with safety monitored relays or monitored
circuits. To achieve the optimum Series 300 defeat resistant
feature of the 301-BT, both the switch circuit (Circuit 1) and the
tamper circuit (Circuit 2) must be connected. An optional third
circuit can be provided to indicate at the panel which guard is
open.
Notes
• Environmental: Pollution Degree II
• Correct use of this control device is an essential part of
proper machine cycle control.
• Failure to follow all instructions could lead to serious bodily
injury or death.
• Maintenance to be done by qualified personnel only
• The connecting cables between the INT devices and the
switches must be located in an IP 23 type enclosure
(minimum).
• The mounting for the switch and the actuator magnet must
be accomplished per this specification.
• Non-removable hardware must be used for installation.
• The housing of the 300-BT must be connected to the PE
(Primary Earth) ground circuit via a lock washer on the
mounting screw. The PE ground symbol must be placed
adjacent to the screw.
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: Dimensions
Installation
Use non-removable screws, bolts, or nuts to mount the switch
and actuator. Do not over-torque mounting hardware.
1. Position the switch and actuator so the labels are reading
in the same direction (see Figure 2).
2. Mount the switch on the stationary frame of the machine
and mount the actuator on the moveable guard, door or
gate. Keep the switch and actuator within the listed sense
range. (See Ordering Information.) See Figure 3 for
recommended mounting configurations.
3. Mounting on a ferrous material will affect the sense range
a minimum of 50%. However, a 1/4" non-ferrous spacer
positioned under the magnet and/or switch should restore
most of the lost sense range.
4. For best protection against operator defeat, mount with
non-removable screws, bolts or nuts. See ordering
information for details.