PAGE 10
3.1. DS1 Setup Switch (Cont.)
(DS1-2) Selects the PLC Monitor System baud rate. OFF = 19.2K, ON=38.4K.
(DS1-3) Selects sensor output mode. OFF= voltage , ON= current.
Note:
1) The voltage mode should be used if the sensor is an addressable
type.
2) Voltage mode output of 0.1 volts represents 0 PPM and 3.0 volts
represents 50 PPM full scale.
3)
Do not use Current Mode Operation because the Audible/
Visual Alarms will affect the loop current.
4) Place DS6 to agree with the mode switch
(DS1-4) Selects sensor full scale span range. OFF= 25 PPM, ON=50 PPM
(DS1-5) Selects sensor calibration gas value OFF = 25 PPM, ON= 50 PPM
(DS1-6) Enables the sensor setup mode to allow setting the warn, alarm and zero
offset levels using the setup potentiometer (R15).
OFF= SETUP MODE ENABLED,
ON= SETUP MODE OFF.
(DS1-7,8) These two switches are used according to the truth table above to select
the warn or alarm value that is to be set using the SETUP potentiometer
(R15). To set one of these values, place DS1-6 switch to the OFF
position. The display will now read the current value given by the Setup
Adjust potentiometer(Figure1). The value idicated will be the previously
used position of the Setup Adjust potentiometer, not necessarily the value
of the currently selected parameter. Next, configure switches DS1-7,8
according to the above table. Using a small screwdriver, adjust potent-
iometer R15 until the desired value is displayed. Now briefly activate the
test/calibrate switch. The display will blink the setup value three times
indicating that the displayed value has been saved. You may now select
another parameter to set using the same procedure. Once all the values
have been set, return the DS1-6 switch position to ON.
3.2. DS2 Cell Polarity
DS2 is for
FACTORY USE ONLY
. It is used to match the sensor cell polarity for
each gas in the MC-4231 series.
DS2 IS HARDWIRED FOR + POLARITY
(1-5, 2-3).
3.3. DS3 2 Wire/4 Wire Comm
DS3 allows the MC-4231 to operate with either a 2 wire monitor system interface
such as the MC-4000 system or a 4 wire monitor system.
DS3 IS HARDWIRED
FOR 2 WIRE COMM (2-4, 5-6).
