BURKERT 20023767 (Type 6281) is a servo-assisted 2/2-way diaphragm valve. A minimum differential pressure is always required for the valve to function. Various diaphragm materials and circuit functions are available depending on the actual application. The standard brass body meets European drinking water requirements. For other markets, dezincification-resistant brass is available. The range includes a variant with a stainless steel body. To reduce electrical power consumption during operation, coils with integrated Kick-and-Drop (KD) electronics featuring double coil technology are available. The valve can be supplied with manual operation for easy maintenance and commissioning.

General Technical Data

Feature	Description
Orifice	DN 10...DN 50
Body material	Brass acc. to DIN EN 50930-6, stainless steel (dezincification resistant on request)
Seal material	NBR, EPDM, FKM
Inner valve parts	Stainless steel, brass, plastic (PPS)
Thermal insulation class	Polyamide coil class B, Epoxy coil class H
Duty cycle	100 % continuous operation
Switching time	Opening: 0.1...1.5 s, Closing: 0.2...4 s
Operating voltage	24 V DC, 24 V UC, 24 V 50/60 Hz, 230 V UC, 230 V 50/60 Hz
Voltage tolerance	±10 %
Degree of protection	IP65 with cable plug, cable connection and terminal box
Installation	As required, preferably with actuator upright

Circuit Functions

Symbol	Description
A (NC)	Circuit function A (CF A) 2/2-way solenoid valve Servo-controlled Normally closed
B (NO)	Circuit function B (CF B) 2/2-way solenoid valve Servo-controlled Normally open

Special Instructions for Circuit Function B

Special instructions for valves circuit function B (NO) with exhaust port G1/8 on the solenoid (CF05/MX62): The valve is open when there is no power. The medium also flows out via the exhaust port on the solenoid. Valves of this type are therefore only suitable for compressor relief.

Approvals and Conformities

• Explosion Protection: ATEX (II 2G Ex mb IIC T4 Gb, II 2D Ex mb IIIC T130 °C Db) and IECEx.
• North America (USA/Canada): UL Listed for Hazardous Locations, UL Recognized, CSA approved.
• Drinking Water: Suitable for use in drinking water applications (PF39, PF36).
• DNV GL Classification: Accepted for installation on all vessels classed by DNV GL.
• Oxygen: Optional suitability for gaseous oxygen.
• VDE: Certificate of conformity with factory surveillance.

Material Specifications

No.	Element	Material
1	Coil	Polyamide or epoxy
2	Stopper	Stainless steel 1.4113
3	Shading ring	Cu (brass variant), Ag (stainless steel variant)
4	Magnetic core	Stainless steel 1.4113
5	O-ring	NBR, FKM, EPDM
6	Core seal	NBR, FKM, EPDM
7	Spring	Stainless steel 1.4310
8	O-ring	NBR, FKM, EPDM
9	Diaphragm	NBR, FKM, EPDM
10	Diaphragm holder	PPSGF40, DN 50: brass and stainless steel
11	Valve body	Brass acc. to DIN EN 50930-6 or stainless steel 1.4408 (CF8M)

Dimensions (Standard Threaded Variant)

Note: Dimensions in mm. The dimensions F1 and G1 apply to G thread. The dimensions F2 and G2 apply to NPT thread. The dimensions F3 and G3 apply to Rc thread.

Coil size	H	J	K	M	O
5	32	20.5	45	41	3.4
6	40	23.5	51	41.4	3.8

Installation and Operation

Risk of injury from high pressure and electric shock

• Before loosening lines or valves, switch off the pressure and vent the lines.
• Before reaching into the device or the system, switch off the power supply and secure it against reactivation.
• Observe the applicable accident prevention and safety regulations for electrical devices.

Manual Override (Optional)

To manually operate the valve, the hand lever must be turned to a vertical position below the solenoid. Do not over-rotate the hand lever. When the hand lever is actuated, the valve can no longer be switched electrically.

Electrical Connection

Screw the cable plug tight (for approved types see data sheet), ensuring a maximum torque of 1 Nm. Check that the valve seal is correctly seated. Connect the protective conductor and check electrical continuity between the solenoid and body.