Fair Child India Private Limited

The Model 1500 Positive Bias Relay is designed for applications that require an output pressure that is the sum of a controlled input signal plus a fixed bias. This pneumatic relay provides high output flow at an output pressure that represents the input signal pressure plus a preset bias. The output of the relay is the sum of the spring bias, set with the Range Screw, plus a pneumatic input signal. (Po = Ps + K); where Po is output pressure, Ps is signal pressure, and K is the spring constant set by the Range Screw.

Specifications

• Max Supply Pressure: 250 psig [17 BAR]
• Max Output Pressure: 150 psig [10 BAR]
• Flow Capacity: 150 SCFM (255 m3/HR)
• Accuracy: 0.5 psi (typ)

Features

• Control sensitivity of 1" water column
• Large Supply and Exhaust Valves
• Soft Supply and Exhaust Valve seats
• A balanced Supply Valve
• Aspirator Tube design
• A separate Control Chamber
• Unit construction

Benefits:

• Allows use in precision applications
• Provides high forward and exhaust flows
• Minimizes air consumption
• Minimizes the effect of any supply pressure variation
• Compensates downstream pressure droop under flow conditions
• Isolates the diaphragm from the main flow to eliminate hunting and buzzing
• Allows you to service the Model 1500A without removing it from the line

The Model 85D Multi-Stage Biasing Relay is a precision control combining the sensitivity of a precision pressure regulator with positive biasing capability. This compact, pilot-operated device offers unusually high output capacity with minimal air consumption, while providing excellent protection against supply or output pressure variations. The versatile Model 85D is recommended for use in systems requiring precision pressure maintenance and instrument biasing, in dead end service and instrument panel supply applications. The basic mathematical expression for the Fairchild Model 85D is PO = PS + K where PO is output pressure, PS is signal pressure and K is the spring constant.

Specifications:

• Max Supply Pressure: 250 psig [17 BAR]
• Max Output Pressure: 150 psig [10 BAR]
• Flow Capacity: 14 SCFM (23.8 m3/HR)
• Accuracy: 0.10 psi (typ)

Features

• Two Stage Pilot Operation
• 14 SCFM flow capacity in a small size unit
• Low air consumption
• Compact size
• Available in 1/8", 1/4" and 3/8" standard port sizes

Benefits

• Allows precise control of set points
• Allows use in applications requiring high flow and/or fast response
• Preserves air and other costly gases
• Permits installation where space is limited
• Versatility makes it easy to design into new and existing applications

The Model 15 Positive Bias Relay is designed for applications that require an output pressure that is the sum of a controlled input signal plus a fixed bias. This pneumatic relay provides an output pressure that represents the input signal pressure plus a preset bias. Mathematically Po = Ps + K where Po is output pressure, Ps is signal pressure and K is the spring constant. This unit, available in several bias range configurations to meet a variety of output requirements, offers excellent sensitivity and high flow capacity in a small volume. The Fairchild Model 15 Pneumatic Biasing Relay is well suited to a variety of control applications, including range shifting, and tension control, and pressure control from a remote location.

Specifications

• Max Supply Pressure: 250 psig [17 BAR]
• Max Output Pressure: 150 psig [10 BAR]
• Flow Capacity: 40 SCFM (68 m3/HR)
• Accuracy: 0.15 psi (typ)

Features:

• Sensitive to 1/4" Water Column variation
• Balanced Supply Valve
• Aspirator Tube
• Flow Capacity of 40 SCFM (68 m3/HR)
• Separate Control Chamber
• Mounting Bracket available

Benefits

• Permits use in high precision applications
• Minimizes the effects of supply pressure variation
• Minimizes downstream pressure droop under flow conditions
• Allows use in applications requiring high flow and/or fast response
• Isolates the diaphragm from the main flow, eliminating hunting and buzzing
• Quick and easy field installation

Designed for applications that require an output pressure that is the sum of a controlled input signal plus or minus a fixed bias, Fairchild's Model 14 Biasing Pneumatic Relay provides versatility in its ability to provide either positive or negative biasing in a single unit. The output of the Model 14 relay is the sum of the spring bias, set with the Range Screw, plus a pneumatic input signal. (Po = Ps K); where Po is output pressure, Ps is signal pressure, and K is the combined spring constant.

Specifications

• Max Supply Pressure: 250 psig [17 BAR]
• Max Output Pressure: 100 psig [7 BAR]
• Flow Capacity: 40 SCFM (68 m3/HR)
• Accuracy: 0.3 psi (typ)

Features:

• Control sensitivity of 1/2" water column
• Balanced Supply Valve
• Aspirator Tube design
• Separate Control Chamber
• Mounting Bracket available
• Canadian Registration Number (CRN) certification

Benefits:

• Allows use in precision applications
• Minimizes the effects of supply pressure variation
• Minimizes downstream pressure droop under flow conditions
• Isolates the diaphragm from the main flow to eliminate hunting and buzzing
• Easy to install in the field
• Certification for use in all Canadian territories and provinces