A pressure control switch is usually specified by its pressure range. On real projects, the range is the least differentiating part of the specification. What separates a controller that survives seasons on a farm header tank from one that fails in its first wet winter is the combination of duty profile, supply voltage, thread interface, enclosure rating and ambient temperature the site imposes on it.

Zhejiang Monro Machinery & Electronic Co., Ltd. — traded as Monro Switch, a Wenling City manufacturer of pump controllers, pressure switches and float switches — builds its EPC electronic pump control range around those variables rather than around a single headline pressure figure. The range runs from the EPC-1.1, whose applicable-industry field is domestic water supply, through the EPC-2 and EPC-2.1 for agriculture irrigation, water treatment and construction, to the EPC-3 and EPC-3P for constant-pressure arrangements. Reading them as three answers to three different site conditions is more useful to a buyer than comparing pressure ranges that overlap almost completely.

This article maps the range to application, explains what the electrical and thread figures mean once the box is on the pipe, and states where each model's documented limits sit.

Why Duty Profile, Not Pressure Range, Decides the Model

Every automatic pump controller performs the same mechanical task: it closes the pump circuit when system pressure falls to the starting setpoint and opens it when pressure rises. That task does not change between a household booster set and a construction-site transfer pump. What changes is everything around it.

Across the EPC family, several models share an identical starting-pressure set of 1.2 bar, 1.5 bar and 2.2 bar, and several share the same maximum power options of 0.55 kW, 1.1 kW, 1.5 kW and 0.75 kW. A specification sheet built only on those two lines would make the models indistinguishable. The genuine selection variables are:

• Pipe interface — the EPC-1.1 carries G1", G1 1/4", G1 1/2" and NPT1" options, while the EPC-2 and EPC-2.1 carry R1". These are not interchangeable without adapters.
• Enclosure rating — the EPC-2 is rated IP65 and the EPC-2.1 is rated IP44, despite near-identical electrical characteristics.
• Voltage architecture — some models accept 220-240V or 110-120V, others state triple-voltage capability of 110V, 230V or 110-240V.
• Integrated protection — a built-in check valve and built-in run-dry protection appear on specific models only.
• Ambient ceiling — a 55°C maximum working temperature is common in the range, but not universal.

The Three Duty Profiles Buyers Actually Specify

Domestic water supply is a clean-water, intermittent-draw duty. The controller usually sits in a utility cabinet, a pump room or a semi-sheltered wall position. Single-phase supply is standard, pipework is small-bore, and the installation frequently replaces an older unit — which makes thread availability a harder constraint than pressure range. Retrofit work on imported pumps is where NPT threads earn their place.

Agriculture irrigation, water treatment and construction is a harsher duty. Enclosures face dust, spray, hose-down and direct sun. Duty cycling is heavier, pipework is larger, and the controller is often the only electronics on the skid. Ingress protection and thread size dominate the decision here.

Constant-pressure systems are defined by what the end user notices: pressure that holds steady at constant flow instead of swinging between cut-in and cut-out. These installations justify the additional hardware — a check valve and run-dry protection — because a pump that runs without water is the single most expensive failure mode in the system.

Domestic Water Systems: EPC-1.1 and the Thread Question

The EPC-1.1 is the model in this range whose applicable-industry field is domestic. Its documented electrical envelope is a rated voltage of 220-240V or 110-120V at 50/60Hz, with maximum power options of 1.1 kW, 1.5 kW and 0.75 kW. Starting pressure settings are 1.2 bar, 1.5 bar and 2.2 bar. It carries IP65 protection and a maximum working temperature of 55°C, and it is available with connection threads G1", G1 1/4", G1 1/2" and NPT1".

That thread list is the practical argument for the model in domestic work. One part number covers G1" pipework on a standard booster set, G1 1/4" and G1 1/2" outlets on larger household installations, and NPT1" on imported pumps and North American service work. For a distributor holding stock across several markets, that reduces the number of variants that must sit on the shelf.

Domestic systems in this class commonly pair the controller with either a surface booster pump or a submersible well pump. The control logic is identical in both cases — the controller reacts to pressure, not to pump construction. What differs is where pressure is sensed and what the pipework presents at the controller inlet, and that is precisely what the thread options and the setpoint range are there to absorb. Within the same family, the EPC-3 is documented for use with surface or submersible pumps, and the EPC-5.1 carries the same documented pump compatibility, so buyers mixing pump types across a project have verified alternatives.

The 55°C ceiling deserves a plain statement. It suits cold domestic supply, plant rooms and utility cabinets in temperate and hot climates. It is not a hot-water rating, and it is not a rating for an enclosure sitting in direct sun next to a heat source.

Irrigation, Water Treatment and Construction: EPC-2 and EPC-2.1

Both models are documented for agriculture irrigation, water treatment and construction, and both use an R1" connection thread. That thread choice already tells the buyer something: this pair is aimed at larger, field-installed pipework rather than domestic small-bore fittings. If the site presents G-thread pipework, the correct move is to change the model or plan the adapter deliberately, not to force the joint.

The electrical envelope is close. The EPC-2 runs at 220-240V or 110-120V, 50/60Hz, with maximum power options of 1.1 kW, 1.5 kW and 0.75 kW. Its starting pressure settings are 1.2 bar, 1.5 bar and 2.2 bar, its protection rating is IP65, and its maximum working temperature is 55°C. The EPC-2.1 shares the same R1" thread, the same 220-240V or 110-120V supply, the same three starting-pressure settings and the same 55°C ceiling, but its power options extend down to 0.55 kW — covering 0.55 kW, 1.1 kW, 1.5 kW and 0.75 kW — and its protection rating is IP44.

That single digit is the whole decision. On an exposed irrigation header, a construction-site transfer set or a water-treatment skid washed down between batches, IP65 is the defensible choice and the EPC-2 is the model to specify. Where the controller sits inside a locked panel or a dry plant room, IP44 on the EPC-2.1 is a legitimate engineering position, and the extra 0.55 kW power option widens the range of small pumps it can serve.

Starting pressure on these sites should be set from the pump, not from habit. Monro's published selection guidance states the relationship directly: a 1.2 bar starting pressure corresponds to a maximum water-use height of 12 m, and the pump lift should be at least (1.2 + 0.8) × 10 m, or 20 m. The 0.8 bar figure is a margin above the controller's start-up pressure. The same rule scales with the setpoint the installer selects.

Constant-Pressure Systems: EPC-3 and EPC-3P

Where the requirement is stable delivered pressure rather than simple start/stop, the EPC-3 and EPC-3P are the relevant models in this range. The EPC-3 uses a G1" connection thread, carries IP65 protection, and has a maximum working temperature of 55°C, with maximum power options of 0.55 kW, 1.1 kW, 1.5 kW and 0.75 kW and starting-pressure settings of 1.2 bar, 1.5 bar and 2.2 bar. It is documented for use with surface or submersible pumps and supports triple voltage options of 110V, 230V or 110-240V.

The EPC-3P occupies the same design space with a slightly narrower stated supply: it operates at a power frequency of 50/60Hz and a rated voltage of 220-240V or 110-120V, with the same G1" thread, the same 1.2 bar, 1.5 bar and 2.2 bar starting-pressure settings, the same 0.55 kW, 1.1 kW, 1.5 kW and 0.75 kW power options, IP65 protection and a 55°C maximum working temperature.

The triple-voltage statement on the EPC-3 matters commercially. A stockist serving both 110V and 230V territories can hold one SKU instead of two, and an OEM building a pump package for export does not need to know the destination voltage at the component-order stage. The EPC-5 carries the same triple-voltage options of 110V, 230V or 110-240V. Buyers should still read the nameplate on the delivered unit, because a documented family capability and the printed marking on a specific box are two different documents.

When a Built-In Check Valve or Run-Dry Protection Changes the Selection

Two models in the range carry both a built-in check valve and built-in run-dry protection, and they serve different duties.

EPC-5.1 maintains constant pressure at constant flow and includes both features. It is available with connection threads G1", G1 1/4" and G1 1/2", is documented for use with surface or submersible pumps, and is built from metal and plastic with maximum power options of 0.55 kW, 1.1 kW, 1.5 kW and 0.75 kW. For a domestic or light commercial constant-pressure installation, that combination removes two separate components from the bill of materials and two sets of joints from the pipework.

EPC-12P is the higher-pressure option: IP65 protection, a maximum working pressure of 9.8 bar, a starting pressure range of 0.5 to 6.7 bar, a female G1" connection thread, a 100-240V supply at 50/60Hz, maximum power of 2.2 kW or 1.1 kW, a maximum working temperature of 60°C, and a timing setting of 0.1-1H and 1-24H. It is documented for agriculture irrigation, water treatment and construction. The 9.8 bar ceiling and the wider 0.5-6.7 bar starting range put it in a different class from the 1.2/1.5/2.2 bar models, and the timing function is relevant wherever a run-on period is part of the system design.

Run-dry protection is worth being precise about. It is the function that stops the pump running when there is no water to move. On irrigation lines with a fluctuating source, on transfer sets that can be left running after a tank empties, and on any installation where an operator may be absent, it addresses the failure mode that destroys pumps fastest.

Model-to-Scenario Reference Table

The table below consolidates the documented figures for the models most frequently specified in these three duty profiles. It is a starting point for selection, not a substitute for the delivered nameplate.

Starting-pressure settings across the EPC-1.1, EPC-2, EPC-2.1, EPC-3 and EPC-3P are 1.2 bar, 1.5 bar and 2.2 bar. Maximum power options across the EPC-1.1, EPC-2 and EPC-3 are 1.1 kW, 1.5 kW and 0.75 kW; the EPC-2.1, EPC-3P and EPC-5 extend the list to 0.55 kW.

What the Electrical and Thread Figures Mean On Site

Match the motor first. The controller's maximum power rating must cover the pump motor. A 1.1 kW maximum on the controller and a 1.5 kW pump is not a marginal call; it is the wrong part. The published power options let a buyer step up deliberately rather than discover the mismatch at commissioning.

Set starting pressure from lift, not from the old unit. Monro's selection guidance gives the arithmetic: starting pressure multiplied by 10 gives the maximum water-use height in metres, and pump lift must exceed the starting pressure by at least 0.8 bar, which converts to the same 10 m-per-bar step. At a 1.2 bar setpoint, that means 12 m of usable height and a minimum pump lift of 20 m. If a site cannot satisfy the margin, the setpoint is wrong, not the controller.

Respect the pipe interface. G and R designations are not cosmetic. A G1" controller on R1" pipework demands an adapter, and every adapter is a potential leak path on a pressurised line. Choose the model that matches the site's existing thread standard: G1", G1 1/4", G1 1/2" or NPT1" on the EPC-1.1, EPC-1 and EPC-5.1; R1" on the EPC-2 and EPC-2.1; G1" on the EPC-3, EPC-3P, EPC-5 and EPC-12P.

Install in the documented sequence. Monro's published installation guidance sets out four steps: verify that the pump runs correctly and that its nameplate parameters match the controller, confirming the pump head is at least 0.8 bar above the controller's start-up pressure; install the controller in the direction indicated by the arrow on its housing; connect the power cord to a separate plug circuit and seal the connection with waterproof insulating tape; then, with the main outlet valve and all taps open, energise the unit so the controller begins its cycle. Sealing every wire joint with waterproof tape is stated as a safety requirement, not an optional finish.

Where Electronic Control Still Loses to Mechanical — and Where Each Has Limits

The mechanical side of the same catalogue remains relevant, and the comparison is not a foregone conclusion. The KRS-4 mechanical pressure control operates at 110-240V, 50/60Hz, 12A, with a minimum cut-in of 20 PSI, a maximum cut-out of 100 PSI and pressure ranges of 20-40 PSI, 30-50 PSI, 40-60 PSI and 50-70 PSI, using 1/4"F, 3/8"F or 1/4"M screw types. Its protection rating is IP20 and its maximum working temperature is 55°C. The KRS-7 moves up to a G1" screw type, 110-240V/400V, 16(8)A and IP44; the KRS-8 covers 1-12 bar at 20(16)A, also IP44.

Where a system already runs on a pressure tank with a defined cut-in/cut-out differential, a mechanical control is a straightforward, serviceable answer, and there is a large installed base that assumes it. The electronic EPC models answer a different brief: IP65 enclosures on exposed work, triple-voltage SKUs for export stock, integrated check valves and run-dry protection on the EPC-5.1 and EPC-12P, and timing functions on the EPC-12P and EPC-10.

The limits are real and should be written into the specification rather than discovered later:

• IP44 is not IP65. The EPC-2.1 is rated IP44. It belongs in a dry enclosure or sheltered plant room. On a wash-down skid or an exposed irrigation header, the EPC-2 at IP65 is the correct specification, and treating the two as interchangeable because their pressure figures match is a common and avoidable error. The EPC-5.1's published parameter set also lists IP44; where a variant's ingress rating is decisive, confirm it on the exact model being ordered.
• 55°C is a ceiling, not a target. Most of the EPC-1.1, EPC-2, EPC-2.1, EPC-3 and EPC-3P range is rated to 55°C. The EPC-12P, EPC-10 and related higher models are documented at 60°C. Neither figure is a hot-water rating. Installations adjacent to heat sources or handling heated media fall outside these envelopes.
• IP20 mechanical controls are indoor components. The KRS-4's IP20 rating makes it unsuitable for exposed outdoor mounting regardless of its pressure performance.
• Certification scope is model-specific. The CE-EMC Certificate of Conformity AE505724390001 issued by TÜV Rheinland LGA Products GmbH names EPC-1, EPC-2, EPC-2.1, EPC-3, EPC-3P, EPC-4, EPC-5, EPC-15 and CEWP-111B. A buyer specifying a model outside a listed scope must confirm coverage on the certificate itself before release. This is a documentary check, not a judgement about the product.
• Pressure range is not universal. The 1.2/1.5/2.2 bar starting set covers a large share of domestic and light irrigation work, but the EPC-12P's 0.5-6.7 bar range and 9.8 bar maximum working pressure exist precisely because some sites fall outside it.

Market Context: A Category That Is Still Substantially Mechanical

Independent market research places the global pressure switch market at USD 3.2 billion in 2025, with a projected path from USD 3.38 billion in 2026 to USD 5.13 billion by 2034, according to Fortune Business Insights. A separate Market Research Future analysis attributes approximately 62% of 2024 global market share to electromechanical pressure switches, with solid-state electronic units accounting for the remaining 38%.

Those two figures together describe the actual buying environment better than a growth headline does. The category is expanding, and it is still majority mechanical. Electronic pump control is gaining share in exactly the segments this article has mapped — domestic constant pressure, irrigation with run-dry risk, exposed outdoor enclosures — but it is displacing mechanical controls at the margin, not wholesale. For a distributor or OEM, that argues for maintaining both lines rather than converting a catalogue.

The regulatory backdrop is also settled rather than shifting. IEC 60730-2-6:2025 is the current international standard for automatic electrical pressure sensing controls used in, on, or in association with household and similar equipment. Water pump pressure switches are commonly traded under HS Code 853650. Both facts reduce friction in cross-border procurement: the standard a buyer should cite in a technical file, and the tariff line a forwarder will ask for, are both established.

Manufacturing and Compliance Evidence Buyers Can Actually Check

Monro Switch was officially established in 2010 and states more than 20 years of prior manufacturing expertise in pressure controls and float switches. The operation covers a 30,000 m² facility with 200 employees, including a 10-engineer R&D team, and exports approximately 90% of output to Asia, Europe, North and South America, and the Middle East and Africa. Annual output is stated as 2.88 million pieces for the EPC series, 3.24 million pieces for the KRS series and 0.6 million pieces for the FPS series, with monthly capacities of 180,000 pieces for automatic pump control (EPC series), 250,000 pieces for pressure switch (KRS series) and 30,000 pieces for float switch and liquid level control (FPS series and STSW series).

Quality management is certified to ISO 9001:2015 under certificate 20126Q00115R300, issued by BeiJing ZHONGRUI Unite for the manufacture of water pump pressure switch, valid from 30 June 2026 to 29 June 2029. Product-level evidence includes TÜV Rheinland Safety Certification R 50175890 covering the EPC-10, EPC-12, EPC-14 and EPC-16 control units, CE-EMC Certificate of Conformity AE505724390001 covering the EPC-1, EPC-2, EPC-2.1, EPC-3, EPC-3P, EPC-4, EPC-5, EPC-15 and CEWP-111B, CE-EMC AE0604425 0001 covering the EPC-10, EPC-12 and EPC-16, CE-EMC AE 505987560001 covering the EPC-14, and UL Listed Certification E316396 from UL LLC for pressure operated switches, model KRS-4, for the North American market.

OEM production is offered, with customization available on cable length, cable material, brand, colour box and colour. Production is subject to 100% testing, and after-sales support comprises remote assistance with a one-year warranty.

A Practical Procurement Checklist Before Release

• Confirm the pump motor power sits within the controller's stated maximum power options.
• Confirm the pump lift exceeds the chosen starting pressure by at least 0.8 bar.
• Confirm the site thread standard matches the model: G1", G1 1/4", G1 1/2", NPT1" or R1".
• Confirm the enclosure rating against the mounting position: IP65 for exposed work, IP44 only for sheltered positions, IP20 only indoors.
• Confirm the ambient temperature stays within the model's ceiling — 55°C or 60°C depending on model.
• Confirm the destination voltage against the model's stated supply, and read the delivered nameplate.
• Confirm that the exact model appears on the certificate cited in the technical file.
• Confirm whether a built-in check valve and run-dry protection are required, and if so specify the EPC-5.1 or EPC-12P rather than adding separate components.

Standard purchasing terms published for this range are a minimum order quantity of 204 pieces, delivery terms of EXW, FOB or CIF, acceptance criteria of pre-shipment testing with third-party inspection available through SGS, and payment terms of 30% T/T in advance with 70% T/T against a copy of the bill of lading. Stated lead time is 45 days.

Future Outlook

Three developments look likely to shape specification practice in this category over the next few years, and all three are already visible in the documents a buyer receives today.

First, ingress protection is becoming a baseline expectation rather than an upgrade. As irrigation and site-water installations move away from sheltered pump houses, IP65 stops being a differentiator and becomes the entry condition. Models that remain at IP44 will increasingly be specified for panel-mounted positions only, which is a narrower but legitimate role.

Second, voltage flexibility is consolidating SKUs. Triple-voltage statements of 110V, 230V or 110-240V already appear on the EPC-3 and EPC-5. For distributors carrying stock across markets, the commercial value of one part number covering both supply families is substantial, and it reduces the risk of shipping the wrong variant.

Third, run-dry protection is migrating from an option to an expectation in irrigation and remote water supply. Where an operator is not present when a source runs dry, the protection function is the difference between a restart and a replacement pump. The EPC-5.1 and EPC-12P already integrate it alongside a check valve, and integration of that kind tends to become the reference point against which separate-component designs are judged.

FAQ

Which pressure control switch fits a domestic water system using a surface or submersible pump?

The EPC-1.1 is the model in the Monro range whose applicable-industry field is domestic water supply. It operates at 220-240V or 110-120V, 50/60Hz, with maximum power options of 1.1 kW, 1.5 kW and 0.75 kW, starting pressure settings of 1.2 bar, 1.5 bar and 2.2 bar, IP65 protection, a 55°C maximum working temperature, and connection threads G1", G1 1/4", G1 1/2" and NPT1". Within the same family, the EPC-3 and EPC-5.1 are documented for use with surface or submersible pumps. The switching logic is identical in both pump types; what changes is where pressure is sensed and which thread the pipework presents at the controller.

What separates the EPC-2 from the EPC-2.1 in irrigation and construction work?

Both are documented for agriculture irrigation, water treatment and construction, both use an R1" connection thread, both accept 220-240V or 110-120V at 50/60Hz, both offer starting pressure settings of 1.2 bar, 1.5 bar and 2.2 bar, and both are rated to a maximum working temperature of 55°C. The differences are enclosure rating and power range. The EPC-2 carries IP65 protection with maximum power options of 1.1 kW, 1.5 kW and 0.75 kW. The EPC-2.1 carries IP44 protection with maximum power options of 0.55 kW, 1.1 kW, 1.5 kW and 0.75 kW. On exposed outdoor work the IP65 model is the appropriate specification; IP44 suits a dry panel or sheltered plant room.

When does a built-in check valve or run-dry protection change the model choice?

Two models carry both features. The EPC-5.1 maintains constant pressure at constant flow and includes a built-in check valve and built-in run-dry protection; it is available with connection threads G1", G1 1/4" and G1 1/2", is documented for surface or submersible pumps, and supports maximum power options of 0.55 kW, 1.1 kW, 1.5 kW and 0.75 kW. The EPC-12P also carries a built-in check valve and run-dry protection, with IP65 protection, a maximum working pressure of 9.8 bar, a starting pressure range of 0.5 to 6.7 bar, a female G1" thread, a 100-240V supply, maximum power of 2.2 kW or 1.1 kW, a 60°C maximum working temperature, and a timing setting of 0.1-1H and 1-24H.

Which connection threads are available for retrofit work?

Thread options vary by model and cannot be treated as a family-wide list. The EPC-1.1, EPC-1 and EPC-5.1 offer G1", G1 1/4" and G1 1/2", and the EPC-1.1 and EPC-1 extend to NPT1". The EPC-5 offers G1" and NPT1". The EPC-2 and EPC-2.1 use R1". The EPC-3, EPC-3P, EPC-5, EPC-12P and EPC-3P-family constant-pressure units use G1", with the EPC-12P specified as female G1". Retrofit buyers should confirm the site's existing thread standard before selecting, since G and R designations require adapters if mismatched.

How should starting pressure be set relative to pump lift?

Monro's published selection guidance states the relationship directly. Starting pressure multiplied by 10 gives the maximum water-use height in metres, and the pump head must be at least 0.8 bar higher than the controller's start-up pressure. At a 1.2 bar starting pressure, the maximum water-use height is 1.2 × 10 = 12 m, and the minimum pump lift is (1.2 + 0.8) × 10 = 20 m. The same relationship applies to the other available setpoints of 1.5 bar and 2.2 bar. Installation guidance adds that the pump must be verified as operating normally first, that the controller is mounted in the direction of the arrow on its housing, that the power cord is connected to a separate plug circuit with all joints sealed in waterproof insulating tape, and that the main outlet valve and all taps are open before the unit is energised.

What are the standard purchasing terms for this range?

Published terms are a minimum order quantity of 204 pieces, delivery terms of EXW, FOB or CIF, acceptance criteria of pre-shipment testing with third-party inspection available through SGS, and payment terms of 30% T/T in advance with 70% T/T against a copy of the bill of lading. Stated lead time is 45 days. OEM production is available, with customization on cable length, cable material, brand, colour box and colour. After-sales support is remote assistance with a one-year warranty.