Model T200U-NOy Option Manual Addendum
26 07303C DCN6646
The external Pump is capable of maintaining the reaction cell pressure at less than
5.0
In-Hg-A. If a higher pressure is noted, the Pump may need servicing. Check the
Pump and pneumatic system for leaks or rebuild the Pump.
CAUTION!
Never operate the analyzer without the ozone destruct component properly
seated and connected within the pneumatic path. The ozone destruct is
integrated into the converter case, at the exhaust of the reaction cell, inside
the instrument.
The sample flow as measured at ports NO IN (1) and NOy IN (2) at the rear of
the analyzer should be 1000 100 cc/min.
See Figure 1 for component locations.
The heater, thermocouple, and converter guts assembly is designed to be replaced
as a single unit. Check Figure 4 for the assembly location.
CAUTION!
The converter operates at 315°C. Severe burns can result if not enough time is
allowed for the assembly to cool. Do not handle assembly until it is at room
temperature.
1. Turn off the power to the 501Y at its front panel ON/OFF switch.
2. Allow the external Converter to cool.
3. Disconnect the gas fittings and power cable from the internal box containing
the heater, thermocouple and converter guts assembly (Figure 4).
4. Remove the entire box from the Converter shelter.
a. Remove the pneumatic fittings.
b. Remove the guts assembly box fr om the chassis by loosening the 4
captive screws that secures the assembly to the chassis.
5. Remove bottom bracket and re-attach it to the replacement guts assembly.
6. Install the box with guts assembly back into the analyzer.
7. Re-attach the electrical and pneumatic fittings. Leak check the assembly
when completed.