Thermo Scientific UCI-100, Operating Instructions Manual, Page: 56 / 62

Universal Chromatography Interfaces
UCI-50 and UCI-100
Page 50 Operating Instructions
8.3 Digital Inputs
Fig. 19: Digital inputs (9-pin D-Sub female connector)
Pin Port Signal Level
1 Input-1 TTL
2 Input-2 TTL
3 Input-3 TTL
4 Input-4 TTL
5 Input-5 TTL
6 Input-6 TTL
7 Input-7 TTL
8 Input-8 TTL
9 Ground GND
Tip:
Internal device resistors keep the digital input level at + 5 V (pull-up
resistance). Therefore, it is possible to use a contact closure relay, without an
additional voltage source. This closure has to be installed between GND and
the respective digital input. Once the relay is shut, the digital voltage is
grounded.
The relay is under a low current of about 50 µA. If the signal source is active,
that is, emitting voltage, verify the correct polarization of the digital input. The
ground of the signal source must be connected to the ground of the UCI. The
digital output of the signal source must be connected to the digital input of the
UCI.