BURKERT 378346 is a 7-bank modular pneumatic valve block from the Type 8640 system, configured with a 19 mm station width and equipped with Type 5470 rocker solenoid valves. Built on modular MP05 polyamide base segments, the block provides common pneumatic supply and exhaust channels while allowing individual valve actuation through single wiring connections. The unit operates within a pressure range of 2.0 to 10.0 bar, supplying a nominal airflow rate ($Q_{Nn}$) of 300 l/min per station through bottom-oriented D6 push-in working connections.

System Architecture and Modular Design

BURKERT 378346 consists of interlocking pneumatic base modules framed by dedicated left and right connection units. The modular structure eliminates custom piping between adjacent valves through integrated internal distribution channels for supply channel 1 (P) and exhaust channel 3 (R).

Item	Component Designation	Function Description
1	Left connection module	Pneumatic supply inlet and exhaust port interface
2	Latch tab	Mechanical positioning guide for adjoining base blocks
3	Latch hook	Snap-locking retention hook for rigid module interlocking
4	Base module (3-fold)	Multi-station pneumatic intermediate body with shared channels
5	Right connection module	End plate termination module or auxiliary pressure stage separator
6	Base module (2-fold)	Multi-station pneumatic intermediate body
7	Exhaust channel 3 (R)	Shared exhaust manifold line
8	Supply channel 1 (P)	Shared pneumatic supply pressure channel
9	O-ring	Module inter-channel elastomer seal

Assembly relies on lower latch hooks snapping into the preceding module's grooves, followed by upper latch hook engagement. Each module interface is sealed using two lubricated O-rings to prevent pressure loss across the internal channels.

Valve Unit Configuration (Type 5470)

The individual valve stations feature Type 5470 solenoid valves driven by integrated Type 6106 rocker pilot valves. A tilting armature supported by a pivot bearing executes minimal angular displacement inside the pilot body, actuating the pneumatic diaphragm without frictional slide wear or need for base lubrication.

Item	Designation	System Assignment
1	Pilot valve Type 6106	Rocker-style electromagnetic pilot control unit
2	Exhaust port 3	Common internal venting line (R)
3	Pressure port 1	Common internal pneumatic supply line (P)
4	Working port 4	Service output port B (actuator line)
5	Working port 2	Service output port A (actuator line)
6	Manual override	Mechanical override switch for testing and maintenance
7	Cable plug Type 2516 / 2506	DIN EN 175301-803 Form C electrical plug interface

Port Numbering Reference

• Port 1: Pneumatic pressure supply input (G 1/4 connection on end plate).
• Port 2 and Port 4: Dedicated service/working outputs equipped with D6 push-in couplings on the valve bottom.
• Port 3: Common exhaust outlet (G 1/4 connection on end plate).

Manual Override Operation

Each Type 5470 valve incorporates an integrated manual override to actuate the valve mechanics during commissioning or electrical downtime.

To engage manual mode, press the manual override down and rotate it 90° clockwise until mechanical stop. The override locks in position without automatic return. Manual operation must only be executed when electrical power is switched off. Unlock the override fully before resuming normal electrical control.

Circuit Functions and Conversion

Type 5470 valves are available as standard 4/2-way valves (Circuit function G) or 3/2-way valves (Circuit functions C and D). A 4/2-way valve can be converted in the field into a 3/2-way valve by sealing one working port with a dedicated plug stopper.

Port 2	Port 4	Resulting Circuit Function	Function State Description
Closed	Open	Circuit Function C (CF C)	3/2-way valve, normally closed (NC) in rest position
Open	Closed	Circuit Function D (CF D)	3/2-way valve, normally open (NO) in rest position

Technical Specifications

Specification Parameter	Value / Range
Station Pitch / Width	19 mm per station
Number of Valve Stations	7-bank (7 slots)
Orifice Size	DN 4.0 mm
Flow Rate $Q_{Nn}$ (Air)	300 l/min (at +20 °C, 6 bar inlet, 1 bar Δp)
Operating Pressure Range	2.0 bar to 10.0 bar (overpressure to atmospheric)
Pilot Pressure Requirement	2.0 to 10.0 bar (must reach at least 70% of operating pressure)
Minimum Pressure Difference	2.0 bar minimum differential between port 1 and port 3
Supply Port 1 (P) / Exhaust Port 3 (R)	G 1/4 female thread
Working Ports 2 (A) and 4 (B)	Push-in fittings for 6 mm outer diameter tubing (bottom exit)
Operating Voltage	24 V DC (±10% allowable voltage tolerance)
Residual Voltage Ripple	Max. 1 Vss
Power Consumption per Valve	1 W, 2 W, or 3 W (24 V DC standard)
Operating Duty Cycle	100% continuous duty (ED)
Fluid Compatibility	Filtered compressed air (particle size max. 10 μm), neutral gases
Air Quality Standard	ISO 8573-1:2010, Class 7.4.4
Medium Temperature Range	0 °C to +50 °C (operation restricted to dried air below 0 °C)
Ambient Operating Temperature	0 °C to +55 °C
Storage Temperature	-40 °C to +55 °C (-20 °C to +60 °C in dry condition)
Assembly Degree of Protection	IP20 overall; IP65 on individual valves with Type 2516 cable plug
Body / Seal Materials	Polyamide (PA) valve body / NBR elastomer seals

Operating Pressure and Differential Limits

The pneumatic pilot unit requires an inlet pressure between 2.0 and 10.0 bar, maintaining at least 70% of total operating pressure. Ensure a minimum pressure differential of 2.0 bar between supply port 1 and exhaust port 3. Operation at temperatures below 0 °C is strictly restricted to dried compressed air.

Continuous Operation Maintenance

When continuous operating cycles are interrupted for extended periods, perform at least 1 to 2 mechanical switching operations per day throughout downtime to preserve diaphragm seating and rocker responsiveness.

Mechanical and Pneumatic Installation

BURKERT 378346 can be mounted on standard industrial DIN rails or bolted directly to flat control panel walls.

DIN-Rail Installation

1. Hook the upper locating groove of the valve block over the top edge of an EN 50022 standard rail (35 x 7.5 mm or 35 x 15 mm).
2. Snap the lower clamping pieces onto the bottom edge of the standard rail.
3. Tighten the fastening screws on the lower clamping brackets.

Wall Installation

Secure the valve block directly against a panel backplate or mounting frame using M4 fasteners inserted through the lateral connection module mounting holes.

Fastening Torques and Assembly Limits

Joint / Port Connection	Connection Thread / Type	Recommended Torque	Maximum Torque
Supply connection 1 (P), Exhaust 3 (R)	G 1/4	4.0 to 7.0 Nm	20.0 Nm
Auxiliary ports / valve outlets	G 1/8	3.0 to 6.0 Nm	7.0 Nm
Valve body to base module screws	2x M2 / M3 fasteners	0.6 ±0.1 Nm	0.7 Nm
Cable plug Type 2516 fastening screw	Center screw Form C	0.3 Nm	1.0 Nm
Solenoid coil rotation screws	M2 coil fasteners	Step 1: 0.1 ±0.05 Nm Step 2: 0.2 ±0.05 Nm	0.25 Nm

Fastening Precautions

Do not use the solenoid coil as a lever arm when tightening threaded pneumatic fittings. Use appropriate open-ended wrenches on the provided module flats. Avoid pipe wrenches.

Solenoid Coil Reorientation (180°)

Valves arrive factory-assembled. If local cable routing requires an alternate connector exit angle, the coil can be rotated 180°:

1. Loosen the M2 retaining screw and withdraw the coil assembly from the valve body.
2. Rotate the coil 180° on its seat.
3. Replace the coil onto the valve body and retighten the M2 screw in two increments: step 1 to 0.1 ±0.05 Nm, step 2 to 0.2 ±0.05 Nm.
4. Verify protective ground conductor continuity between the coil connector ground blade and the valve assembly.

Pneumatic Line Connection and Push-in Fittings

Pneumatic lines must satisfy minimum mechanical requirements: hardness ≥ 40 Shore D (DIN 53505 / ISO 868), outer diameter to DIN 73378 (tolerance within ±0.1 mm), clean surface, cut square at 90°, and completely deburred.

Hose Material	Tube Outer Diameter (OD)	Permitted OD Tolerance (ISO 14743:2020)
Polyamide (PA)	3 mm to 10 mm	±0.08 mm
Polyamide (PA)	12 mm to 16 mm	±0.10 mm
Polyurethane (PU)	3 mm to 8 mm	±0.10 mm
Polyurethane (PU)	10 mm to 16 mm	±0.15 mm

Minimum Tensile Retention Force (DIN ISO 14743:2020)

Hose Outer Diameter (OD)	3 mm	4 mm	6 mm	8 mm	10 mm	12 mm	14 mm	16 mm
Min. Tensile Force: Polyamide (PA)	60 N	70 N	120 N	170 N	250 N	300 N	300 N	350 N
Min. Tensile Force: Polyurethane (PU)	25 N	50 N	100 N	150 N	200 N	200 N	250 N	300 N

Tubing Retention with Softer Hoses

When using flexible polyurethane (PU) tubing subject to temperature fluctuations or lateral pulling stress, insert internal support sleeves (ID 20099400) into tube ends prior to inserting into push-in collars.

Electrical Installation and Commissioning

BURKERT 378346 operates via individual single wiring. Each valve station is actuated independently through an industry-standard Type 2516 or Form C cable plug adhering to DIN EN 175301-803 (formerly DIN 43650 Form C).

Plug Installation and Ground Check

1. Verify flat elastomer gasket placement between the cable plug connector and the coil base contacts.
2. Fasten the central screw to a tightening torque of 0.3 Nm.
3. Measure electrical continuity across the protective conductor path:

Test Parameter	Test Standard Limit
Ground Path Resistance	Maximum 0.1 Ω
Test Voltage	12 V DC
Test Current	1.0 A

Impulse Control Design Configuration

For bistable impulse coil configurations, observe strict polarity and minimum electrical pulse durations of 50 ms:

• Positive (+) on Pin 2, Negative (-) on Pin 1: Opens pilot valve (ports 1 to 4 connected on CF C, 1 to 3 / 2 to 3 on CF G).
• Positive (+) on Pin 1, Negative (-) on Pin 2: Closes pilot valve (ports 4 to 3 connected on CF C, 1 to 2 / 4 to 3 on CF G).

Maintenance and Troubleshooting

Before undertaking servicing, isolate electrical supplies, depressurize the pneumatic system, and exhaust line manifolds completely.

Observed Fault	Potential Cause	Corrective Measure
Valves fail to switch	No operating voltage or voltage below lower limit	Verify 24 V DC supply and pin contact seating at Type 2516 plug.
	Manual override locked in non-zero position	Return manual override detent to zero resting position.
	Supply pressure insufficient (< 2.0 bar)	Restore upstream compressor and regulator pressure to ≥ 2.0 bar.
Delayed switching or continuous exhaust blow-off	Upstream line volume or flow restricted	Enlarge supply pipe diameter; check filter regulators and shut-off valves.
	Block pressurized while valves energized	Depressurize system and apply pneumatic supply before energizing coils.
	Excessive back pressure from clogged silencers	Clean or replace exhaust silencer elements on port 3 (R).
	Contamination in pilot valve or pneumatic seat	Blow out internal galleries using clean pulsed air; replace pilot cartridge.
Pneumatic leakage between modules	Damaged or missing O-rings at block interfaces	Disassemble module bay, renew O-rings (lubricated), and re-engage latches.
Leakage beneath valve body	Missing or improperly seated valve body flat seal	Check valve interface recess, verify 3 O-rings/profile seal, torque screws to 0.6 Nm.

Disassembly Procedure

1. Standard rail removal: Loosen bottom clamping piece screws by approximately 4 full turns and lift the complete assembly upwards off the rail profile.
2. Multi-block module separation: Insert a flat-blade screwdriver into the disassembly notch on the front edge to release the upper latch hook, then slide the sub-block laterally.
3. Hose removal: Depress the push-in connector thrust collar evenly against the body and withdraw the pneumatic hose.