Fairchild TXI7800 Installation, Operation And Maintenance Instructions

FAIRCHILD TXI7800/TXI7850
EXPLOSION-PROOF I/P TRANSDUCERS
Installation,Operation and Maintenance Instructions
Standard Range Unit
Extended Range Unit
GENERAL INFORMATION
The Model TXI7800/TXI7850 Explosion-Proof I/P Transducer transmits a pneumatic signal which is linearly proportional to a DC
input signal from electronic control devices. The Transducer uses low powered microelectronics and pressure feedback control
to provide a stable, accurate pneumatic output for the operation of valve actuators.
I
NSTALLATION
The Model TXI7800/TXI7850 can be mounted directly onto a flat surface using the two tapped mounting holes in the mounting
face of the housing. For more information, see Figure 2.
TXI7800/TXI7850, Installation with the "N" Option.
NOTE: For Hazardous Location in Potentially Explosive Atmosphere Installations
1. Tapped exhaust required for installation in Class 1, Division 2/Zone 2 (European Union) classified locations with
group D/Group IIA (European Union) gases such as Natural Gas and Methane-Industrial as the pressure supply medium.
2. The explosion-proof pipe nipple seal (N option) supplied with this unit is an integral component of the design safety
of this version and must not be removed. Use caution to avoid marring the threads on the pipe nipple which voids the
explosion-proof integrity of the device.
3. Gases used as the pressure supply medium in hazardous location applications must be compatible with the elas­
tomer indicated in Materials of Construction.
A mounting Kit is available to mount the TXI7800/TXI7850 on a flat surface or on a 2" pipe. For more information, see Figure 3.
MAINTENANCE
To clean the Orifice, use the following procedure:
1. Shut off the valve that is supplying air to transducer. It is not necessary to remove the Transducer from the air line.
2. Remove the Orifice Assembly from the unit. For more detailed information see View A.
3. Clean with alcohol and dry with compressed air.
4. Lubricate O-Rings on Orifice Assembly (4) with silicone grease or equivalent lubricant before reassembling.
NOTES:
Parts must be completely dry before reassembling.If the standard maintenance procedure does not correct the trouble, a service
kit containing a replacement diaphragm and orifice assembly is available, see Figure 5.
Figure 2. TXI7800/TXI7850 Outline Dimensions.
Materials of Construction
Body and Housing . Cromate Treated
Aluminum
Orifice . . . . . . . . . . Aluminum
and Sapphire
Trim . . . . . . . . . . . . Stainless Steel, Brass
and Zinc Plated Steel
Sintered Elements . Stainless Steel
Elastomers . . . . . . .Nitrile
Finish . . . . . . . . . . . Epoxy Powder Coating
NOTE: Unused IN and OUT Ports are plugged
.