Appendix

C.I/O Connections

A15-pin female D-sub connector is included with the instrument to connect digital I/O to the SQM-160 Relay I/O connector. The figure below shows the solder side pin assignments for the connector.

1

8

9

1 5

Relay I/O Connector Rear View

Relays are rated for 125VAC or 30VDC, 2A maximum. Inputs can be activated either by connecting to a switch and shorting to Ground, or they can be driven by a TTL compatible signal. These are not isolated inputs! The voltage level applied must be limited to between 0 and +5 volts with respect to Ground.

Pins

Type

Description

1,2

Relay

Crystal Fail Relay, contacts closed when all

 

 

enabled sensors have failed.

3,4

Relay

Timer Setpoint, contacts closed when timer

 

 

reaches Zero from its programmed value.

5,6

Relay

Shutter Relay, contacts closed when shutter

 

 

is open.

7,8

Relay

Thickness Setpoint Relay, contacts close

 

 

when thickness value reached.

9

Input

Zero Timer Input, grounding this pin will zero

 

 

the timer.

10

Input

Zero Thickness Input, grounding this pin will

 

 

zero the thickness reading.

11

Input

Close Shutter Input, grounding this pin will

 

 

close the shutter.

12

Input

Open Shutter Input, grounding this pin will

 

 

open the shutter.

13,14,15

Ground

 

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Image 34
Sigma SQM-160 manual Appendix O Connections, Relay I/O Connector Rear View, Pins Type Description