Status Led's; Watchdog Circuitry; Valve Control; Table 6-4. Relay Pca Status Led's - Teledyne T200 User Manual

STATUS LED'S

Sixteen LEDs are located on the analyzer's Relay PCA to show the current status on the
various control functions performed by the Relay PCA (see Figure 5-15). Their on/off
states are described in Table 6-4; their functions and fault descriptions were presented in
Table 5-6.

Table 6-4. Relay PCA Status LED's

LED
D1 Cycles ON/OFF every 3 Seconds
under direct control of the analyzer's CPU.
D2 Reaction cell heater is heating
D3 Heating
D4
D5 1 Converter heater is heating
D6
D7 Z/S valve OPEN to span gas flow
D8 Sample/Cal valve OPEN to
calibration gas flow
D9 A/Z valve: sample gas flow BYPASSES the reaction cell
D10 NO/NOx valve: gas flow routed THROUGH the converter
D11 2 Dual span gas valve (1 or 2): OPEN to SPAN 1 gas inlet
D12 Pressurized span shutoff valve: Span gas flow SHUTOFF
3
D13 4 Pressurized zero shutoff valve: Zero gas flow SHUTOFF
D14 – 16 Spare
1 Only active when the optional internal span gas generator is installed.
2 Only active when the dual pressurized span option is installed.
3 Only active when one of the pressurized span gas options is installed.
4 Only active when one of the pressurized zero gas options is installed.

WATCHDOG CIRCUITRY

The most important of the status LED's on the relay board is the red I
LED. It is controlled directly by the analyzer's CPU over the I
the Relay PCA watches the status of D1. Should this LED ever stay ON or OFF for 30
seconds, indicating that the CPU or I
automatically shuts all valves and turns off all heaters.

VALVE CONTROL

The relay board also hosts two valve driver chips, each of which can drive up four valves.
The main valve assembly is the NO/NO
right in front of the NO
• These two valves are actuated with 12 V supplied from the relay board and under the
control of the CPU through the I
Additional valve set options also controlled by the CPU via the I
can be included. (see Sections 2.3.2.3, 2.3.2.4, and 2.3.2.5 regarding these valve sets).
083730200A DCN7962
STATUS WHEN LIT
(ENERGIZED STATE)
2 C bus has stopped functioning, this Watchdog Circuit
converter housing.
2
C bus.
2
Teledyne API T200 NO/NO
STATUS WHEN UNLIT
(DEFAULT STATE)
Not Heating
Not Heating
Not Heating
Valve OPEN to zero gas flow
Valve OPEN to
sample gas flow
Sample gas flow is routed THROUGH
the reaction cell
Gas Flow BYPASSES the converter
OPEN to SPAN2 inlet
Span gas flow OPEN
Zero gas flow OPEN
2 C bus. Special circuitry on
- Auto-zero solenoid valve component mounted
X
C bus, and the relay PCA
2
/NO Analyzer with NumaView™ Software
2 x
C bus watch-dog
2
203