Description
Overview
The Type 200 Precision Air Relay is a pilot-operated, multistage 1:1 relay designed to accurately reproduce a signal pressure with either positive or negative bias adjustment. It provides consistent repeatability while maintaining stable output pressure across changing operating conditions.
Output control and stability are maintained through a high-gain, servo-balanced control mechanism activated by a highly sensitive stainless steel measuring capsule. The Type 200 controls output pressure to within 0.1% and is available in several configurations for internal or external bias adjustment and increased relief capacity.
With a bias range from -30 psig to +100 psig, output capability up to 120 psig, and sensitivity of 1/8 inch water column, the Type 200 is well suited for precision pressure control, remote pressure regulation, volume boosting, and gas mixing applications.
Key Features
- Pilot-operated multistage 1:1 relay design
- Positive and negative bias adjustment capability
- Controls output pressure to within 0.1%
- Highly sensitive stainless steel measuring capsule
- High-gain servo-balanced control mechanism
- Consistent repeatability
- Stable output under variable operating conditions
- Internal bias adjustment standard on Type 200
- External bias adjustment available on Type 200EB
- High relief capacity available with Type 200HR
- Extra high relief capacity available with Type 200EHR
- Up to 15 scfm exhaust capacity with Type 200EHR
- 1/4″ and 3/8″ port sizes
- NPT and BSP porting available
- Optional tapped exhaust
- Oxygen-compatible configurations available by factory consultation
Performance Characteristics
- Output Range: 2-120 psig (0.14-8 bar)
- Bias Range: -30 psig (-2 bar) to +100 psig (6.7 bar)
- Maximum Output Pressure: 120 psig (8 bar)
- Maximum Supply Pressure: 150 psig (10 bar)
- Maximum Signal Pressure: 120 psig (8 bar)
- Flow Capacity: 14 scfm (396 Nl/min) at 100 psig supply and 20 psig signal
- Type 200 Exhaust Capacity: 3 scfm (85 Nl/min)
- Type 200HR Exhaust Capacity: 11 scfm (311 Nl/min)
- Type 200EHR Exhaust Capacity: 15 scfm (425 Nl/min)
- Sensitivity: 1/8″ (3.2 mm) water column
- Supply Pressure Effect: Less than 0.005 psig (0.0003 bar) output variation for a 25 psig (1.7 bar) supply pressure change
- Bleed Rate: Less than 0.08 scfm (2.3 Nl/min)
- Operating Temperature: -20°F to 160°F (-29°C to 71°C)
- Port Sizes: 1/4″ and 3/8″ NPT/BSP
- Mounting: In-line pipe mounting
- Weight: 1.4 lb (635 g)
These performance characteristics provide precise pressure reproduction, excellent sensitivity, and stable control for demanding pneumatic applications. A minimum output pressure of 2 psig (0.14 bar) is required to provide bleed air to the pilot pressure chamber, so the relay does not regulate below 2 psig. A startup spring maintains a minimum 2 psig output even without signal pressure.
How to Select the Right Configuration
Selecting the correct Type 200 configuration depends on the required bias adjustment method, exhaust capacity, port size, and application requirements.
- Select the standard Type 200 for internal bias adjustment and general precision relay applications
- Select the Type 200EB when external bias adjustment is required for easier access to the bias setting
- Select the Type 200HR when increased exhaust capacity and faster downstream pressure release are required
- Select the Type 200EHR for extra high relief capacity up to 15 scfm
- Select the Type 200EB/HR when both external bias adjustment and high relief capacity are required
- Choose 1/4″ porting for smaller pneumatic lines and standard installations
- Choose 3/8″ porting when a larger connection size is preferred
- Select the Tapped Exhaust option when a 10-32 tapped exhaust vent and barbed bleed screw are required
- Select BSP Porting when BSP process connections are required
- Consult the factory when oxygen-compatible construction is required
For additional guidance:
Applications
The Type 200 Precision Air Relay is designed for pneumatic systems requiring accurate signal reproduction, bias control, and stable pressure output.
- Operation of multiple devices from one controlled source
- Remote pressure control
- Volume boosting
- Gas mixing
- Pneumatic instrumentation
- Process control systems
- Signal pressure reproduction
- Industrial automation equipment
- OEM pneumatic systems
- Applications requiring positive or negative pressure bias
The application guidance and biasing diagrams on page 2 illustrate how positive and negative bias settings shift output pressure relative to the input signal while maintaining the relay’s 1:1 relationship.
Models & Configurations
Standard Type 200 Models
- Type 200: Standard relay with internal bias adjustment
- Type 200EB: External bias adjustment
- Type 200HR: High relief capacity
- Type 200EHR: Extra high relief capacity
- Type 200EB/HR: External bias adjustment with high relief capacity
Model Numbers
- 200-BC = Type 200, 1/4″ NPT, 2-120 psig
- 200-CC = Type 200, 3/8″ NPT, 2-120 psig
- 210-BC = Type 200HR, 1/4″ NPT, 2-120 psig
- 210-CC = Type 200HR, 3/8″ NPT, 2-120 psig
- 211-BC = Type 200EHR, 1/4″ NPT, 2-120 psig
- 211-CC = Type 200EHR, 3/8″ NPT, 2-120 psig
- 220-BC = Type 200EB, 1/4″ NPT, 2-120 psig
- 220-CC = Type 200EB, 3/8″ NPT, 2-120 psig
- 230-BC = Type 200EB/HR, 1/4″ NPT, 2-120 psig
- 230-CC = Type 200EB/HR, 3/8″ NPT, 2-120 psig
Available Options
- E = Tapped Exhaust, 10-32 tapped exhaust vent and barbed bleed screw
- U = BSP Porting, 1/4″ or 3/8″
- Oxygen Compatible = Consult factory for ordering information
The ordering table on page 2 lists all standard model, port size, and output range combinations.
Accessories
- 0-15 psi Gauge: P/N 446-725-003
- 0-30 psi Gauge: P/N 446-725-004
- 0-60 psi Gauge: P/N 446-725-001
- 0-160 psi Gauge: P/N 446-725-002
Materials of Construction
- Body: Die-cast zinc alloy with baked enamel paint
- Capsule and Adjusting Screw: Stainless steel trim, brass, and plated steel
- Diaphragms: Buna-N elastomer with polyester fabric
The Type 200 combines a durable zinc-alloy body with precision metallic internal components and Buna-N diaphragms for reliable industrial pneumatic service.
Technical Resources
FAQs
What is the Type 200 precision air relay used for?
The Type 200 is used to accurately reproduce a pneumatic signal pressure while adding or subtracting an adjustable bias. Typical applications include remote pressure control, volume boosting, gas mixing, and operation of multiple devices from one controlled source.
How accurate is the Type 200?
The Type 200 controls output pressure to within 0.1% and provides consistent repeatability through its high-gain servo-balanced control mechanism.
What is positive bias on the Type 200?
With positive bias, output pressure is directly proportional to the input signal plus the bias setting. Output pressure will not fall below the value of the positive bias setting regardless of signal pressure.
What is negative bias on the Type 200?
With negative bias, output pressure remains at its minimum until the signal pressure exceeds the negative bias value. Above that point, the relay reproduces the signal pressure minus the selected bias.
What is the bias adjustment range?
The Type 200 provides a bias adjustment range from -30 psig (-2 bar) to +100 psig (6.7 bar).
What is the output pressure range?
The Type 200 has an output pressure range of 2-120 psig (0.14-8 bar).
Why does the Type 200 not regulate below 2 psig?
A minimum output pressure of 2 psig is required to provide bleed air to the pilot pressure chamber. A startup spring therefore maintains at least 2 psig output even when no signal pressure is present.
What is the difference between the Type 200 and Type 200EB?
The standard Type 200 uses an internal bias adjustment screw to help prevent casual tampering. The Type 200EB provides an external bias adjustment screw for easier access to the bias setting.
What is the difference between the Type 200HR and Type 200EHR?
The Type 200HR provides up to 11 scfm exhaust capacity, while the Type 200EHR provides extra high relief capacity up to 15 scfm for faster downstream pressure blowdown.
What port sizes are available?
The Type 200 is available with 1/4″ and 3/8″ NPT porting. BSP porting is also available as an option.
