Teledyne Analytical Instruments 3020 M, Руководство по эксплуатации

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Paramagnetic Oxygen Analyzer Operation
Teledyne Analytical Instruments
53
samplings and displays this difference as Slope on the screen. It takes
several seconds for the first Slope value to display. Slope indicates rate
of change of the Span
reading. It is a sensitive indicator of stability.
#### % Span
Slope=#### ppm/s
When the
Span
value displayed on the screen is sufficiently stable,
ENTER it. (Generally, when the
Span
reading changes by 1 % or less
of the full scale of the range being calibrated for a period of ten minutes
it is sufficiently stable.) Once you ENTER it, the
Span
reading changes
to the correct value. The instrument then automatically enters the
ANALYZE function.
4.9 The ALARMS Function
The Model 3020M is equipped with 2 fully adjustable
concentration alarms and a system failure alarm. Each alarm has a relay
with a set of form “C" contacts rated for 3 amperes resistive load at 250
V ac. See Figure in Chapter 3,
Installation and/or the Interconnection
Diagram included at the back of this manual for relay terminal
connections.
The system failure alarm has a fixed configuration described in
chapter 3 Installation .
The concentration alarms can be configured from the front panel as
either high or low alarms by the operator. The alarm modes can be set as
latching or non-latching , and either failsafe or non-failsafe , or, they can
be defeated altogether. The setpoints for the alarms are also established
using this function.
Decide how your alarms should be configured. The choice will
depend upon your process. Consider the following four points:
1. Which if any of the alarms are to be high alarms, and which if
any are to be low alarms?
Setting an alarm as HIGH triggers the alarm when the oxygen
concentration rises above the setpoint. Setting an alarm as LOW
triggers the alarm when the oxygen concentration falls below the
setpoint.
Decide whether you want the alarms to be set as:

Both high (high and high-high) alarms, or