Section 8 - Arctic Configurations; Arctic Option - Oldham OLCT 200 User Manual

SECTION 8 - ARCTIC CONFIGURATIONS

8.1 ARCTIC Option

OLCT 200 3-wire models may be ordered with a special ARCTIC configuration to
include a 175 ohm 4-watt heater / temperature controller circuit mounted to the back of
the 10-0233 Power Supply PCB (Figure 2-5). In addition, when equipped with a locally
mounted 10-0247 Smart Sensor Head (Figure 2-16) ARCTIC Smart sensors are
available with a 1-watt heater / temperature controller for warming the sensor
compartment. This is important since many electrochemical sensors have a low
temperature rating of only -20C. If incoming 10-30VDC power is at least 24VDC, the
ARCTIC option extends OLCT 200 operation down to -55C.
Important! ARCTIC OLCT 200's consume more power when it is cold! When
temperature inside the OLCT 200 enclosure is below -25C the 175 ohm 10-0233 PCB
heater is connected across the incoming DC power terminals. When an ARCTIC
Smart Sensor is installed, its 1-watt heater is connected across the OLCT 200's
internal 5VDC power supply when Sensor Temp is below the Setpoint (see section
8.1.1). These additional loads must be considered when sizing the installation's DC
power supply.
8.1.1 ARCTIC Smart Sensor Temperature Setpoint Option
Both the O2/TOXIC and LEL/Current channels (see section 3.1.1) are capable of
accepting ARCTIC Smart Sensors with 1-watt heater / temperature controller circuits.
ARCTIC sensor temperature controllers have a unique address that is automatically
detected by the OLCT 200. This activates the Sensor Temp menu on page 2 of the
channel's main menu as shown below in Figure 8-1. Selecting Sensor Temp and
pressing EDIT opens a window displaying the sensor's current temperature and the 1-
watt heater's Setpoint. When the Sensor Temp value is below the Setpoint value the
heater is on. This feature is helpful in applications where the sensor temperature must
be higher than the ambient temperature to function properly.
Entering YES in the Marker Active menu also activates Marker TX LED, Mark Level,
and Mark As menus. Mark Level allows entering the <3.75mA value (+.2mA) to
detect. Mark As allows entry of the up to 10 digit ASCII message the LCD readout will
display when the Marker is detected. Marker TX LED menu = YES, causes the front
L E L I N P U T 2
L C D Co n t r a s t A d j .
Mo d b u s R S 4 8 5 P o r t
S e c u r i t y
T e c h n i c i a n s ON L Y
S e n s o r T e mp
F i r mw a r e R e v .
Figure 8-1: ARCTIC Sensor Temperature Menu
OLCT 200 User Manual | 67
L E L / MOS
>
>
EDIT
S e n s o r T e mp
>
S e t p o i n t
>
>
T E MP
2 8 . 7 5 ° C
- 0 . 0 0 C
°