Control Unit Operation; System Power Switch And Led; Audible Alarm Switch And Bypass Led; Fuses - Teledyne 1220 Instruction Manual

4 Operation

4.2 Control Unit Operation

4.2.1 System Power Switch and LED

The power to the entire 1220 system is controlled by the System
Power Switch.
The green System Power LED indicates system power status (ON/
OFF).

4.2.2 Audible Alarm Switch and Bypass LED

The Audible Alarm Switch overrides the audible alarm when in the
Bypass position. The red Bypass LED lights when the audible alarm is
bypassed.

4.2.3 Fuses

For fuse replacement/installation, see section 3.3.1 and 3.4.3

4.2.4 RS485 Port

NOTE: This feature is not presently supported--contact the factory for
application assistance.
An RS485 port is provided at the 9-pin D-sub connector. The RS485
port is connected internally to all of the Channel Modules in the system.
4-2
Control Unit - Front View
Teledyne Analytical Instruments
Model 1220