Teledyne 3000 Ultra Trace - PPB oxygen analyzer - Manual (Page 29)

Ultra Trace Oxygen Analyzer Installation 3
3-7 Teledyne Analytical Instruments
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 Ultra Trace 3000 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.
Once a zero or span command is sent, and acknowledged (contact
closes), release it. If the command is continued until after the zero or span is
complete, the calibration will repeat and the Cal Relay Contact (CRC) will
close again.
For example: