LSS-2404
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Trigger Input
The LSS-2404 trigger input is a ground referenced 4.7K ohm resistive termination. It is designed to work with
most outputs on common devices. The voltage mode accepts 3.3 and 24 V logic level voltage with an adjustable
trigger level. In Switched Ground Mode, Trigger Input supports opto-isolators or closed contacts via direct
connection without external components.
Voltage Driven Outputs (TTL or Similar)
The external device’s output can be wired directly to the input with the polarity shown. The input is designed to
work with any input signal voltage level from 5 V to 24 V. Proper triggering can be achieved by adjusting the
trigger level in the software to work with the input signal voltage. The default trigger level is set to 9.6 V,
designed for signal levels ranging from 12 V to 24 V.
For signal levels less than 12 V the trigger level in the software may need to be lowered. The trigger level should
be set to approximately 50-80% of the maximum input signal voltage. Try adjusting the software trigger level up
or down to find a stable operating point.
Trigger signals must be clean and sharp at the 4.7K ohm input termination to the LSS-2404. Be sure the trigger
device supplying the signal and cabling are appropriate to drive the termination. Do not exceed 30 V absolute
maximum at any time or damage may occur to the input.
Switches and Mechanical Contacts
The trigger input is designed to easily work with switches or mechanical contact without any biasing or external
circuitry. Simply connect the switch to the trigger input pins. In the LSS-2404 GUI, check the ground triggered
mode. The LSS-2404 will trigger every time that contact is made between the 2 input pins.
Opto-isolators or Open Collector Transistors with Internal bias
If the opto-isolator has internal biasing built in, it can be connected in parallel directly across the trigger input
contacts with the polarity shown. Keep in mind that the negative trigger input pin is ground referenced.
External Source
Trigger In
