Pressure Switch 220V G 1/2″ M x 1 with Regulator, Two Gauges, Safety Valve and 2 Cocks — Complete Control Kit for Reciprocating Compressor

A problem you have already faced

• A basic pressure switch without a regulator and gauges gives no control of outlet pressure and no protection of tools from over-pressure
• Buying a pressure switch, regulator, gauges and cocks separately wastes time on selection and installation with no guarantee of compatibility
• The unloading valve does not operate after shutdown — the motor starts under pressure and burns out quickly
• No way to set outlet working pressure independently of receiver pressure — spray gun or pneumatic tools run unstably
• After replacing the pressure switch, the compressor does not start or stop — incorrect pressure range or wiring

No outlet regulator is not just unstable spray quality. Excess pressure destroys pneumatic tool seals and triples their wear rate.

What the kit contains and how it works

1. Pressure switch (pressostat) 220V series: electromechanical device monitoring receiver pressure. Starts the motor when pressure drops below the lower setpoint and stops it at the upper setpoint. Single-phase 220 V supply.
2. Unloading valve EV: built into the pressure switch. At every shutdown, vents residual pressure from the discharge line (between the head and the check valve). Allows the motor to start off-load on the next cycle.
3. Pressure regulator (0–8 bar): reduces receiver pressure to the required working pressure at the outlet. Set independently of receiver pressure. Key element for stable operation of spray equipment and sensitive pneumatic tools.
4. Receiver gauge (to 16 bar): shows current receiver pressure. Allows monitoring of fill level and pressure switch operation.
5. Line pressure gauge (to 12 bar): shows outlet pressure — after the regulator. Allows precise adjustment of working pressure for the tool.
6. Safety valve (set at 8 bar): mechanical protection of the receiver against exceeding working pressure. Mandatory per PED 2014/68/EU.
7. Two air cocks: ball valves at the outlet. Allow connecting two consumers simultaneously or shutting off supply without stopping the compressor.

Technical specifications

Expert tip: G 1/2″ M is the male (external) thread at the pressure switch inlet. It screws into the receiver port with female G 1/2″ thread. Do not confuse with G 1/4″ — the diameters are different and direct connection is not possible. Check your receiver port thread before ordering.

How this kit differs from a basic pressure switch

Equivalent products by brand

Note: the 220V series is single-phase, 220 V. Receiver connection is G 1/2″ M (male thread) — different from the G 1/4″ of the basic 4-outlet series. For three-phase 380 V motors use Condor MDR3.

5 parameters to verify when selecting an equivalent:

1. Supply voltage — 220 V single-phase; for 380 V three-phase use MDR3
2. Receiver connection thread — G 1/2″ M (male); the receiver port must be G 1/2″ F (female) to match
3. Regulator included — built into this kit (0-8 bar); not included in the basic 220V F×4 series
4. Pressure range — cut-in/cut-out setpoints must match your compressor operating pressure (to 10 bar)
5. Unloading valve EV — mandatory for reciprocating compressors with a check valve; built into this kit

Why Acvatron SRL — 5 compelling reasons

1. Complete kit — 30-minute installation with no component sourcing

Everything needed for full compressor control in a single body. No time spent finding compatible regulator, gauges and valves — they are pre-assembled, calibrated and ready to connect.

2. Engineering-based selection for your compressor

An Acvatron engineer verifies the compressor model, motor voltage and receiver thread before dispatch. You receive a part compatible with your installation — no wrong thread, no wrong pressure range.

3. In stock in Chisinau

220V series pressure switches with regulator are in stock. Same-day dispatch; next business-day delivery within Moldova.

4. Full pressure switch range: 220V (1 and 4 outlets), MDR3, MDR5

Acvatron SRL stocks all pressure switch types for reciprocating compressors — single-phase and three-phase, with and without regulator, across a range of pressures.

5. Documentation for legal entities

Every kit is supplied with documentation and a wiring diagram. For companies — tax invoice and supply contract.

Application areas

Spray finishing and vehicle service

• Controlling the compressor feeding a spray gun — the regulator (0-8 bar) delivers stable atomisation pressure of 2-4 bar regardless of receiver pressure
• Connecting spray gun and blow gun simultaneously through the two cocks
• Monitoring receiver and outlet pressure — two gauges give a complete picture of system status

Pneumatic tools in workshops and production

• Supplying impact wrenches, grinders and staplers at constant working pressure of 5-6 bar
• Shutting off tool supply without stopping the compressor — ball cocks
• Protecting sensitive tools from over-pressure through the built-in regulator (max. 8 bar)

Woodworking and joinery

• Controlling the compressor for pneumatic nailers and staplers
• Stable pressure for pneumatic clamps and presses
• Quick switching between two consumers without changing fittings

Expert opinion

Vitali Bolucevschi, Chief Engineer, Acvatron SRL — 15 years in the industry:

The 220V series pressure switch with regulator is what should be fitted on any compressor used for spray painting or sensitive pneumatic tools. Without a regulator, receiver pressure feeds directly into the hose — at 8-10 bar the spray gun runs unstably, paint consumption increases by 50% and impact wrench seals wear out twice as fast. Note the connection thread: this model has G 1/2″ M — a male external thread. If your receiver has a G 1/4″ port, you need an adapter or a different kit variant. The most common installation mistake: the unloading valve tube (the small 6 mm tube on the side of the pressure switch) is not connected to the fitting downstream of the compressor check valve. Connect it correctly, otherwise air vents into the room at every shutdown.

Applicable standards: PED 2014/68/EU (safety valve included, set at 8 bar), EN 60947 (pressure switch). Compatible with: ABAC, Fini, Fubag, Bort, Patriot and equivalent 1.5-3 kW 220 V reciprocating compressors.

How to choose the right pressure switch with regulator: a 5-step process

1. Determine the motor supply voltage. 220 V → 220V series (this kit). 380 V three-phase → MDR3 + regulator separately.
2. Check the receiver outlet port thread. Inside diameter approx. 20.9 mm = G 1/2″ F (fits this kit’s G 1/2″ M). Inside diameter approx. 13.2 mm = G 3/8″ F — adapter required or different model.
3. Confirm the unloading valve is present. Mandatory for reciprocating compressors with a check valve. Built into this kit.
4. Determine the required working pressure at the outlet. Spray painting: 2-4 bar. Impact wrenches, drills: 5-6 bar. The built-in regulator covers 0-8 bar.
5. Count the consumers. 1-2 consumers → this kit with 2 cocks. 4 constant consumers → 220V F×4 series with separate regulator.

Handling common objections

“A basic pressure switch is cheaper”

A basic pressure switch without regulator and gauges requires buying a regulator (~EUR 15-25), two gauges (~EUR 8-12), a safety valve (~EUR 5-8) and cocks (~EUR 5-8) separately. Total difference: EUR 35-50, with twice the installation time. This kit is more economical in both cost and effort.

“I am not sure whether G 1/2″ M fits my compressor”

G 1/2″ M is the male external thread on the pressure switch inlet. Your receiver must have a G 1/2″ F (female) port to match. If your receiver has G 1/4″ or G 3/8″ — advise us when ordering: we will select the right thread variant or supply an adapter.

“Why do I need two gauges if I already have one?”

The receiver gauge shows accumulation pressure (to 16 bar) — it tells you how the pressure switch is performing and whether the receiver is full. The gauge after the regulator (to 12 bar) shows actual tool supply pressure. Without the second gauge, precise regulator adjustment to the 2-4 bar needed for spray painting is not possible.

Frequently asked questions

Can a 380 V compressor be connected to this pressure switch?

No. The 220V series is rated for single-phase 220 V supply. Connecting a three-phase 380 V motor to this pressure switch will immediately burn the contacts. For three-phase compressors, use a Condor MDR3 10/10A or MDR3 16/24A, selected according to the motor rated current.

How do I adjust the cut-in and cut-out pressures?

Under the 220V pressure switch cover there are two adjustment springs. The large spring (P) sets the cut-out pressure (upper threshold). The small spring (dP) sets the differential — the gap between cut-in and cut-out. Clockwise rotation increases pressure. Typical factory setting: cut-in 6 bar, cut-out 8 bar, differential 2 bar.

How do I set the regulator to the required working pressure?

Pull the regulator knob up (unlock), turn clockwise to increase outlet pressure, monitor on the line pressure gauge. Set the required value: 3-4 bar for spray painting, 5-6 bar for pneumatic tools — within the regulator’s 0-8 bar range. Push the knob down to lock.

What should I do if the safety valve keeps tripping?

Repeated safety valve operation at 8 bar means receiver pressure is reaching the valve setpoint. Check the pressure switch cut-out setting — if drifted above 8 bar, readjust. If the pressure switch fails to stop the compressor, replace it.