Analyzer components – Yokogawa In-Situ Gas Analyzer TDLS200 User Manual
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IM 11Y01B01-01E-A 6th Edition :Feb 13, 2013-00
<4. ANALYZER COMPONENTS>
Connections of each relay (Common and Normally Open) are routed through the board to field terminals.
The contacts are rated for a maximum of 1A @ 24VDC (or 0.5A @ 125VAC).
The pluggable field terminals are mounted on the lower edge of the board, just to the left side of the DC power
input terminals.
The appropriate relay(s) is actuated when a calibration gas check valve is to be initiated.
Laser Temperature & Current Control
The board has two main laser control function circuits, temperature control and laser current control.
Board Temperature
The board has a temperature sensing chip/circuit that monitors temperature of the board inside the main
electronics enclosure. The sensor is located on the top edge of the Back Plane.
Backplane Circuit Board Power & Signal Routing
The Back Plane carries out several routing functions for both power and signals: I/O for Detect Unit is routed
through the Back Plane from one set of pluggable field terminals (located lower left hand of Back Plane) to the
appropriate destination. Terminals are provided for:
• Analog DC power (x3)
• Raw Detector Signal (differential voltage) (x2)
• Detect Unit Temperature (differential voltage) (x2)
Analog I/O Board outputs the analyzer results and reads input process gas compensation values (pressure and
temperature). The board has power status LEDs as well as voltage test points for the input and
output channels.
• Output channels (three) are ranged 0-20mA. They can be assigned to measured values Oxygen,
Transmission or compensation signal re-transmission.
• Input Channels (two) are used by the analyzer to read active values for process gas temperature
and/or process gas pressure. These are application dependant and may or may not be required
inputs. There are two channels, one for temperature and one for pressure. Each may be used to
read 4-20mA signals that are isolated or to read and loop power (with integral 24VDC) signals.