Chapter 5 Making Safety Interlock Connections - THORLABS ULN15TK User Manual

Ultra-Low-Noise Laser System
Chapter 5 Making Safety Interlock Connections
The ULN15TK is equipped with a remote interlock connector located on the rear panel. In order to enable the
laser, a short circuit must be applied across the terminals of the Remote Interlock connector. This connection is
made available to allow the user to connect a remotely actuated switch to the connector (i.e. an open door
indicator).
The switch that is connected to this interlock must be normally open (N.O.), meaning that it has to be closed in
order for the unit to be enabled. If the switch is changed to an open state, the amplifier will automatically shut
down.
All units shipped from Thorlabs are configured with a shorting device installed in the interlock connector. If you
are not going to use this feature then you can leave the shorting device installed and the unit will operate normally,
as described throughout this manual. If you wish to make use of the interlock feature you will need to acquire the
appropriate mating connector (e.g., a 2.5 mm mono jack, available at most electronics stores) and wire it your
remote interlock switch.
The electrical specifications for the interlock input are shown in the following table.
Specification
Mating Connector
Open Circuit Voltage
Short Circuit Requirements
Interlock Switch Requirements
Rev. A, August 17, 2022
Chapter 5: Making Safety Interlock Connections
Value
2.5 mm Mono Phono Jack
Internal Pull Up to 5 VDC
1.0 mA DC
Must be N.O. Dry Contacts
Under No Circumstances Should Any External
Voltages be Applied to the Interlock Input
Ground
Interlock Circuitry
Page 11