ProMinent Pump Model Code Explained: Series, Identcode and Head Materials

A ProMinent pump model code has two layers. The first is the series name, such as Beta, gamma/X or Sigma, which tells you whether the pump is solenoid driven or motor driven and roughly what capacity range it covers. The second is the long identcode printed on the nameplate, where each position or group of characters stands for one configuration choice: capacity class, liquid end material, valve type, hydraulic connection, power supply and control options. Once you can read both layers, ordering a diaphragm, a valve set or a replacement pump stops being guesswork. This article is written for maintenance technicians and buyers, including anyone holding an old nameplate and trying to find a matching pump.

Start with the series: the drive sets the direction

ProMinent builds a wide range, but on site you mostly meet three groups:

1. Solenoid diaphragm pumps such as Beta, gamma/X and gamma/XL. They cover smaller flows and are common on water treatment skids.
2. Motor-driven diaphragm pumps such as Sigma/1, Sigma/2 and Sigma/3, used for continuous process duty at higher flows and pressures.
3. Special pumps, for example the DUODOS air-operated diaphragm pump for areas without convenient power.

For background on each family, see our pages on the gamma/X solenoid metering pump and the Sigma/1 motor-driven metering pump. Here we focus on the ProMinent pump model code itself.

How to read the ProMinent pump model code

The identcode generally follows this order: series, capacity class, liquid end material, valves and seals, connection, power supply, then options. On solenoid pumps, the series abbreviation is usually followed by a four-digit group. That group is a capacity class. In most cases the first two digits relate to a pressure class and the last two to a flow class. Treat it as a class number, not as an exact rating. Always confirm flow and pressure from the performance table for that exact model.

Right after the capacity group, a three-letter block usually describes the liquid end material combination, written in forms such as PVT, NPE or SST. Those letters cover the head body, valve balls and seals. For sodium hypochlorite, hydrochloric acid or sulfuric acid, this is the part of the ProMinent pump model code you must never swap casually.

Later positions describe the valve design (with or without springs, with or without a bleed valve), the hydraulic connection size, the supply voltage, the cable plug, and options such as external pulse control, level input, relay output or fieldbus.

What each position means

A ProMinent pump model code is not identical across series. Beta and gamma/X, for example, use different option positions and letters. The only reliable method is to copy the complete ProMinent pump model code from the nameplate and check it position by position against the identcode table in that series' operating manual. If a position is not listed in the manual you have, mark it as "per the model manual" rather than guessing from another series.

Three common mistakes when reading the code

The first mistake is reading the capacity class as a rated value and using it to calculate dose. Real output also depends on back pressure and chemical viscosity, so a pump can fall short even at full stroke. The second is ignoring the power supply position. Pumps sourced from another region may arrive with a different voltage or plug. The third is checking the head material but not the valves. Whether there is a bleed valve and what the balls are made of matters a lot with gassing chemicals such as hypochlorite. Reading the full ProMinent pump model code avoids all three.

Matching ProMinent metering pump specifications to your duty

Once the ProMinent pump model code is decoded, map it back to the application:

• The pressure class must exceed the highest injection point pressure with margin.
• Normal flow should sit in the middle of the range so stroke length and frequency both have room.
• The liquid end must suit the chemical, concentration and temperature; viscous chemicals also need the right valve type.
• Control options must match the plant signal: pulse, 4–20 mA or bus. A wrong option means a new control module.

What to check before ordering spares or a replacement

The most common request we receive is "one ProMinent gamma pump, please". Within one series, different capacity classes use different diaphragms and valve sets, and different material codes mean spares cannot be mixed. A safer routine:

1. Photograph the whole nameplate and copy the full identcode and serial number.
2. For diaphragms and valves, quote the capacity class and material block of the ProMinent pump model code.
3. For a complete replacement, also confirm the power and control positions so the new unit connects to the existing wiring.

If the nameplate is worn, the head material marking and connection size give clues, but always confirm with the distributor using the serial number. You can also compare models on our ProMinent brand page and our range of solenoid metering pumps.

Conclusion

A ProMinent pump model code is easy to read once you split it: the series gives the drive and rough range, and the identcode gives capacity class, liquid end material, valves, connections, power and options. The capacity class and the material block matter most for spares and replacements, and everything should be checked against the full code in the manual. If you have an old nameplate and need a match, send us the ProMinent pump model code, chemical and pressure and contact our engineers for a position-by-position check.

FAQ

Is the four-digit number the exact flow and pressure?

No. It is a capacity class linked to flow and pressure. Use the performance table for real values; the ProMinent pump model code only points you to it.

Can I change the liquid end material letters myself?

Not advisable. A new material means a new liquid end, and it should be confirmed against the chemical.

Do diaphragms fit across different series?

Generally no. Size and design differ by series and capacity class, so order by identcode.

The nameplate is missing. How do I find the model?

Give the serial number to the distributor, or estimate from the head connection and housing, then confirm.

Where are ProMinent metering pump specifications most reliable?

In the operating manual and product catalogue for that series, which contain the identcode table and performance data.