BURKERT 20097830 (Type 3281) is a direct-acting electromotive 2-way globe proportional control valve designed for dosing liquids and gases in continuous control loops. Actuation is performed by an integrated linear stepper motor coupled to a threaded drive spindle, eliminating the need for compressed air infrastructure. The motor draws energy only during stroke adjustments and consumes less than 1 W in holding mode, significantly reducing baseline electrical demand. The fluid path remains completely isolated from the actuator mechanism, ensuring clean operation and reliable service life.

Article 20097830 is configured as a process controller variant with an integrated cascaded PID control structure. It combines an RC 1/2" female threaded connection, a 10 mm nominal seat orifice, a flow coefficient Kvs of 2.25 m³/h, and a controlled operating pressure range of 0 to 7 bar(g). Process communication and parameterization operate via the digital Bürkert system bus (büS, based on CANopen), accompanied by a dedicated M12 socket that accepts an external process transmitter signal.

Technical Specifications

Specification Parameter	Technical Value
Article Number	20097830
Valve Type Family	Type 3281 (Electromotive 2-way globe valve)
Circuit Function	Direct-acting 2-way proportional valve, closed-loop control
Port Connection	RC 1/2" internal thread (ISO 7-1 / EN ISO 228-1)
Nominal Seat Diameter	10 mm (3/8")
Flow Coefficient Kvs	2.25 m³/h (water at +20 °C, 1 bar Δp)
Operating Pressure Range	0 to 7 bar(g)
Flow Direction	Against closing direction (below seat, 2 → 1)
Operating Voltage	24 V DC ±10% (max. residual ripple 10%)
Operating Power Consumption	< 1 W holding, max. 12 W operating (short-term 20 W)
Medium Temperature Range	-20 °C to +130 °C
Ambient Temperature Range	-10 °C to +60 °C (observe derating)
Fluid Viscosity Limit	Max. 600 mm²/s (cSt)
Seat Leakage Rate	Class VI according to DIN EN 60534-4
Nominal Pressure Class	PN 25 (DIN EN 1333)
Full Stroke Actuation Time	Approx. 2.5 s (configurable down to 2.2 s or up to 3.2 s)
Positioner Dead Band	±0.5% (corresponding to 1:100 control ratio)
Enclosure Protection Rating	IP54 (with matched mating connectors)
Unit Weight	Approx. 1.1 kg

Operating Principle & Control Architecture

The internal valve spindle is rigidly linked to a precision threaded spindle driven by an electric stepper motor. Rotary motor movements convert into linear stroke action to position the control cone relative to the valve seat. When holding a set position, internal gear holding torque locks the valve spindle in place without motor excitation.

Article 20097830 features integrated process controller electronics operating in cascade control mode. The main control loop runs a configurable PID process algorithm that compares the target process setpoint (SP) against the actual process variable (PV) read from an external sensor. The output of the PID calculation becomes the setpoint position command (CMD) for an inner, auxiliary positioning loop. A contactless, wear-free position sensor tracks the linear actuator position (POS) and feeds it to the inner positioner, which calculates motor steps until control difference Xd2 reaches zero.

The process controller input supports multiple filter stages (0 to 9) to smooth noisy transmitter readings before PID processing:

Filter Stage Setting	Cut-Off Frequency (Hz)	Low-Pass Damping Effect
0	10 Hz	Minimum filter effect
1	5 Hz	Low filtering
2	2 Hz	Standard filtering
3	1 Hz	Moderate filtering
4	0.5 Hz	Medium filtering
5	0.2 Hz	Increased filtering
6	0.1 Hz	High filtering
7	0.07 Hz	High filtering
8	0.05 Hz	Heavy filtering
9	0.03 Hz	Maximum filter effect

Materials of Construction

All media-wetted components comply with EC Regulation 1935/2004 and GB food standards (variable code PL10), making them suitable for sanitary, beverage, and pure gas processing duties.

Item Number	Component Part	Construction Material
1	Housing Cover	Polycarbonate (PC GF10 anthracite)
2	Housing Base	Polyphenylene sulfide (PPS GF40 black)
3	Spindle Guide	High-performance polymer
4	Sliding Washers	High-performance polymer
5	Guide Piece	Stainless steel 1.4305
6	O-Ring	Nitrile rubber (NBR)
7	Compression Spring	Stainless steel
8	Spindle Seal	PTFE (filled) / FKM with spring compensation
9	Pipe	Stainless steel 1.4404
10	Body Seal	Graphite
11	Valve Spindle	Stainless steel 1.4401
12	Control Cone	Stainless steel 1.4571
13	Seat Seal	PTFE sealing washer
14	Valve Seat	Stainless steel 1.4571
15	Valve Body	Cast stainless steel CF3M / 316L

Dimensions

The actuator housing can be rotated continuously clockwise by up to 360° after loosening to align cable entries. The valve body must be open during any rotation or disassembly.

A	B	C	D	E	F	G	H	I	J
76 mm	216 mm	188 mm	84 mm	112 mm	52 mm	66 mm	45 mm	58 mm	20 mm

Port Connection Standard	Thread Size	Thread Depth E (mm)	Face-to-Face Length LM (mm)	Width Across Flats AF (mm)
RC (ISO 7-1)	RC 1/2"	13.2 mm	65 mm	27 mm
G (DIN ISO 228-1)	G 1/2"	14.0 mm	65 mm	27 mm
NPT (ASME B1.20.1)	NPT 1/2"	13.7 mm	65 mm	27 mm

Electrical Connections & Pin Assignment

Article 20097830 features two A-coded M12 circular connectors located on the base of the actuator: one 5-pin plug for digital büS/CANopen communication and power supply, and one 5-pin socket for direct connection of external process sensors.

Digital Fieldbus Port (M12 A-Coded 5-Pin Plug)

Pin	Wire Color (büS Cable)	Pin Assignment	Signal Description
1	Shield	Shielding	Cable shield
2	Red	Supply +	24 V DC ±10%, max. ripple 10%
3	Black	GND	Power supply ground
4	White	CAN_H	Fieldbus CAN high line
5	Blue	CAN_L	Fieldbus CAN low line

Process Actual Value Sensor Port (M12 A-Coded 5-Pin Socket)

Pin	Wire Color (Cable 559177)	Pin Assignment	Signal Specification
1	Brown	Sensor Supply +	24 V DC ±10% auxiliary transmitter power
2	White	Actual Value Input +	0/4–20 mA (60 Ω), 0–5/10 V (22 kΩ), or Frequency (5–2000 Hz)
3	Blue	GND	Sensor ground
4	Black	GND	Ground bridge to Pin 3
5	Grey	Not used	Unassigned

Performance & Flow Characteristics

The Type 3281 series accommodates multiple seat orifices to achieve optimal control rangeability across specific pressure windows. Article 20097830 is built with a 10 mm seat:

Body Construction	Seat Diameter	Control Mode	Port Connection	Kvs Value (m³/h)	Operating Pressure (bar)
Globe	4 mm	Continuous control	1/2"	0.57	0 to 16 bar(g)
Globe	6 mm	Continuous control	1/2"	1.25	0 to 16 bar(g)
Globe	8 mm	Continuous control	1/2"	1.80	0 to 12 bar(g)
Globe (20097830)	10 mm	Continuous control	RC 1/2"	2.25	0 to 7 bar(g)
Globe	15 mm	On/off switching	1/2"	4.45	0 to 3.5 bar(g)
Angle-seat	15 mm	Continuous control	1/2"	3.60	0 to 3 bar(g)
Angle-seat	15 mm	On/off switching	1/2"	4.55	0 to 3.5 bar(g)

Operating Duty Cycle Limits

The duty cycle represents the actual running time of the stepper motor rather than the powered-on duration of the valve electronics. Because frequent setpoint changes increase motor internal heating, operators must verify thermal limits using the derating diagram. Exceeding recommended duty cycle thresholds reduces actuator service life.

Proper Valve Seat Sizing

To maintain the intended linear valve characteristic in real piping systems, ensure that at least 25% of the total system pressure drop occurs across the fully open control valve (Δp_valve > 0.25 · Δp_total). Undersized pressure drops distort linear valve curves into non-linear system curves.

Configuration & Optional Accessories

Configuration, commissioning, and diagnostics for article 20097830 are executed via the Bürkert Communicator software (Type 8920) running on a Windows PC. Communication hooks directly into the büS/CANopen network via a dedicated USB-büS interface stick.

Key software functions include:

• P.TUNE: Automated self-optimization of PID loop parameters (gain factor Kp, reset time Tn, derivative time Tv).
• P.LIN: 20-step automatic linearization of the actual process characteristic.
• CUTOFF: Tightly seals the valve below user-defined setpoints (CUTOFF_min) or opens 100% above set thresholds (CUTOFF_max).
• X.TIME: Limits stroke positioning speed from 2.2 s (Fast) to 3.2 s (Slow 2) to prevent water hammer.
• Diagnostic LED Indication: Switchable between Bürkert standard colors and NAMUR NE 107 diagnostic signaling.

Emergency Fail-Safe Return

Because stepper motor actuators retain their physical position upon sudden loss of power supply, fail-safe emergency homing requires an external capacitive buffer module. The buffer module provides 18 V DC for several seconds during mains interruption, allowing the internal control electronics to drive the valve cone into the pre-configured safety position (SAFEPOS).

Accessory Description	Article Number
USB-büS Interface Set 1 (Type 8923, includes büS stick, terminating resistor, power pack, cables)	772426
USB-büS Interface Set 2 (Type 8923, includes büS stick, terminating resistor, Y-distributor, 0.7 m cable)	772551
M12 Shielded Sensor Cable, 5-pin female connector, 2.0 m length (for process actual value input)	559177
Switched-Mode Power Supply Unit Type 1573 (Phoenix Class 2, 85–240 V AC / 24 V DC, 1.25 A)	772438
Capacitive Buffer Module Type 1573 (maintains 18 V DC to drive valve to SAFEPOS on power outage)	773440
Seat Replacement Assembly Tool Insert (for torque tightening of seats 4 to 10 mm to 20 ±3 Nm)	625604