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Model 14 Positive & Negative Bias Relay
Brand: Fairchild Industrial Products
Designed for applications that require an output pressure that is the sum of a controlled input signal plus or minus a fixed bias, Rotork 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.
Features- Control sensitivity of 1/2" water column allows use in precision applications
- A balanced Supply Valve minimizes the effects of supply pressure variation
- An Aspirator Tube minimizes downstream pressure droop under flow conditions
- A separate Control Chamber isolates the diaphragm from the main flow to eliminate hunting and buzzing
- Mounting Bracket is available
- Canadian Registration Number (CRN) certification for all territories and provinces
Specifications
Pressure Range
- -18-2 psig : -1.2-0.15 bar : -120-15 kPa
- -18-10 psig : -1.2-0.7 bar : -120-70 kPa
- -18-30 psig : -1.2-2 bar : -120-200 kPa
- -18-100 psig : -1.2-7 bar : -120-700 kPa
Pipe/Port Size
- 1/4"
- 3/8"
- 1/2"
Pipe/Port Thread Type
- NPT
- BSPT
Approvals
- CRN
Hazardous Areas
- Acceptable in Zones 1–2 (gas, Groups IIA & IIB) and Zones 21–22 (dust).
Max. Supply Pressure
- 250 psig : 17.0 bar : 1700 kPa
Max. Output Pressure
- 150 psig : 10.0 bar : 1000 kPa
Flow Capacity
- 40 scfm (68 m³/hr) @ 100 psig, 7.0 bar, 700 kPa supply & 20 psig, 1.5 bar, (150 kPa) setpoint.
Supply Pressure Effect
- Less than 0.1 psig : 0.007 bar : 0.7 kPa for a 100 psig : 7.0 bar : 700 kPa change in supply pressure.
Exhaust Capacity
- 5.5 scfm (9.35 m³/hr) where downstream pressure 5 psig : 0.35 bar : 35 kPa above setpoint of 20 psig :1.5 bar : 150 kPa.
Sensitivity
- Less than 1/2” (1.27 cm) W.C.
Ambient Temperature Limits
- -40° F to +200° F (-40° C to 93.3° C)
Relief
- Relieving
- Non-Relieving
Tapped Exhaust Vent
- Tapped
Body & Housing Material
- Aluminum
Elastomers Material
- Silicone
- Viton (Fluorocarbon)
Diaphragm Material
- Nitrile on Dacron
Trim Material
- Brass, Stainless Steel, Zinc-Plated Steel
Pressure Range
- bar: -1.2 to 0.7
- kPa: -120 to 700
- psig: -18 to 100
Environmental Protection
- Acceptable for use in Zones 1 & 2 for Gas Atmosphere, Groups IIA & IIB & Zones 21 & 22 for Dust Atmospheres
Vent
- Straight
- Tapped Exhaust
Relief
- Non-Relieving
- Relieving
Trim Material
- Brass
- Stainless Steel
- Zinc-Plated Steel
Sensitivity
- Less than 1/2 inH₂O (1.27 cm)
Enclosure, Body Material
- Aluminum
Elastomers
- Fluorocarbon (Viton)
- Nitrile on Dacron
- Silicone
Signal or Output Pressure - Maximum
- bar: 10
- kPa: 1,000
- psig: 150
Ambient Temperature Range
- -40° to 93° C (-40° to 200° F)
NPT Connection
- 1/2" NPT Female
- 1/4" NPT Female
- 3/8" NPT Female
Mounting
- None
Supply Pressure Effect
- psig: 0.1 (bar: 0.007, kPa: 0.7) for a psig: 100 (bar: 7, kPa: 700) Change in Supply Pressure
Exhaust Capacity - Relieving Units Only
- 5.5 scfm
- 5.5 scfm (9.35 m³/hour)
- 9.4 m³/hour
BSP Connection
- 1/2" BSPT Female
- 1/4" BSPT Female
- 3/8" BSPT Female
Flow Capacity
- 40 scfm
- 40 scfm (68 m³/hour) psig: 100 (bar: 7, kPa: 700) Supply, psig: 20 (bar: 1.5, kPa: 150) Set Point
- 68 m³/hour
Actuator Type
- Knob Adjust
- Tamper-Proof
Supply Pressure - Maximum
- bar: 17
- kPa: 1,700
- psig: 250
