Teledyne 3300ZB operating instructions Rear Panel Electrical Connectors

Trace Oxygen Analyzer Installation

Figure 3-1: Rear Panel Electrical Connectors

Analog Outputs: There are three DC output signal connectors with screw terminals on the panel. There are two wires per output with the polarity noted. See Figure 3-1. The outputs are:

0–10 V Concentration: Voltage is proportional to oxygen reading, from 0 V at 0 ppm oxygen to 10 V at full scale ppm oxygen. (Full scale = 100% of programmed range).

0–10 V Range ID:	3.33 V = Low Range, 6.66 V = High Range
4–20 mA % Range:	Current is proportional to oxygen reading, from 4
	mA at 0 ppm oxygen to 20 mA at full scale ppm
	oxygen. (Full scale = 100% of programmed
	range).

Alarm Relays: The three alarm circuit connectors are screw terminals for making connections to internal alarm relay contacts. There is one set of contacts for each type of alarm. Contacts are Form C, with normally open and normally closed contact connections capable of switching up to 0.5A at 125 VAC into a resistive load.

The alarm relay circuits are designed for failsafe operation, meaning the relays are energized during normal operation. If power fails the relays de-energize (alarms activated).

The contact connections are indicated diagrammatically on the rear panel as normally closed (NC), common (C), and normally open (NO). Figure 3-2 explains how these act in failsafe operation.

Teledyne Analytical Instruments 11