Teledyne 3000ZA-3X - Trace oxygen analyzer - Manual (Page 33)

Trace Oxygen Analyzer Installation
Teledyne Analytical Instruments 21
Zero: Floating input. 5 to 24 V input across the + and – pins puts the
analyzer into the Zero mode. Either side may be grounded at
the source of the signal. 0 to 1 volt across the terminals allows
Zero
mode to terminate when done. A synchronous signal must
open and close the external zero valve appropriately. See
Remote Probe Connector. (The –C option internal valves
operate automatically.)
Span: Floating input. 5 to 24 V input across the + and – pins puts the
analyzer into the Span mode. Either side may be grounded at
the source of the signal. 0 to 1 volt across the terminals allows
Span
mode to terminate when done. A synchronous signal
must open and close external span valve appropriately. See
Figure 3-5 Remote Probe Connector. (The –C option internal
valves operate automatically.)
Cal Contact: This relay contact is closed while analyzer is spanning
and/or zeroing. (See Remote Calibration Protocol below.)
Table 3-3: Remote Calibration Connections
Pin Function
9 + Remote Zero
11 – Remote Zero
10 + Remote Span
12 – Remote Span
40 Cal Contact
41 Cal Contact
Remote Calibration Protocol: To properly time the Digital Remote Cal
Inputs to the Model 3000ZA Analyzer, the customer's controller must
monitor the Cal Relay Contact.
When the contact is OPEN, the analyzer is analyzing, the Remote
Cal Inputs are being polled, and a zero or span command can be sent.
When the contact is CLOSED, the analyzer is already calibrating. It
will ignore your request to calibrate, and it will not remember that
request.