Teledyne 4020 - Hydrocarbon analyzer User Manual
Page 66
Operation Model
4020
Teledyne
Analytical
Instruments
50
The calibration process will initiate and after a few moments the
LED digital display will indicate the zero or span gas concentration and
the VFD display will inform the user it has finished the calibration.
<Enter>
To accept the calibration, press
calibration and repeat the process, press
The zero (span) process will automatically conclude when the output
is within the acceptable range for a good zero (span). If accepted by the
operator, the analyzer automatically returns to the Analyze mode.
4.6.12 The Alarms Function
The Model 4020 is equipped with 2 fully adjustable concentration
alarms and a non-adjustable system failure alarm. Each alarm relay has a
set of form "C" contacts rated for 3 amperes resistive load at 250 VAC.
See Figure in Chapter 3, Installation and/or the Interconnection Diagram
included at the back of this manual for relay terminal connections. The
alarm relay contacts are accessible to the user from the 50-pin
Equipment Interface connector.
The system failure alarm has a fixed configuration described in
Chapter 3 Installation.
The concentration alarms can be configured from the ALARM
function screen as either high or low alarms by the operator. The alarm
modes are set at the factory as non-failsafe however they can be defeated
by the operator from within the ALARM function screen. In failsafe
mode, the alarm relay de-energizes in an alarm condition. For
non-failsafe operation, the relay is energized in an alarm condition.
The setpoints for the alarms are also established using this function.
Prior to programming the alarms you should decide how they should
be configured. The choice will depend upon your process. Consider the
following points:
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