Short answer: Two types of calibration are carried out on AnTech dosing pumps: capacity calibration, which matches the amount of chemical the pump actually delivers to the value on the display, and sensor calibration, which keeps pH, ORP or free chlorine measurement accurate on measurement-controlled models. Capacity calibration is available in the menu of the Nova D, Nova DMPR and Nova DMİA models. pH/ORP electrodes are calibrated with buffer solutions, and the free chlorine sensor against a reference measurement made with the DPD method. To request calibration, contact us through our contact page or on +9+90 216 606 44 72 / WhatsApp +9+90 532 542 81 24.
An uncalibrated pump or sensor means a system that looks correct on the display but delivers the wrong amount of chemical into the water. Because a measurement-controlled chlorine dosing pump doses according to the value from the electrode, a small deviation in the sensor translates directly into too much or too little chlorine. This page describes the calibration work covered by our chlorine dosing pump service.
What Is Capacity Calibration and How Is It Done in the Nova Menu?
Capacity calibration means measuring the volume the pump delivers under real operating conditions and entering it into the pump. It is needed because the volume an electromagnetic pump delivers with each stroke varies with back pressure. According to catalogue values, the AnTech Nova D 10 L/h 10 Bar Digital Dosing Pump delivers the following flow rates at different pressures:
| Back pressure | Maximum flow | Volume per stroke |
|---|---|---|
| 10 bar | 10 L/h | 0.556 ml |
| 8 bar | 13 L/h | 0.722 ml |
| 5 bar | 15 L/h | 0.833 ml |
| 2 bar | 20 L/h | 1.111 ml |
The same pump can deliver twice as much on a 2 bar line as on a 10 bar line. Without calibration, the L/h value on the display will differ from the actual flow rate in your line. The menus of the Nova D, Nova DMPR 10 L/h 10 Bar and Nova DMİA 10 L/h 10 Bar models include capacity calibration, operating limits and a stroke feedback setting; capacity can be entered as L/h, strokes/minute, strokes/hour or a percentage. The general calibration procedure is as follows:
- The pump is run under real operating conditions, i.e. connected to the injection point and under line pressure.
- The suction assembly is placed in a graduated container filled with chemical.
- The calibration function is started from the menu and the pump delivers for a set period for calibration.
- The volume drawn from the container is read and entered into the menu.
- The pump calculates its subsequent settings from this measurement; the value on the display is then compared with daily consumption.
The order of the menu steps may differ depending on the software version; during calibration we follow the sequence in the model’s user manual. All models in the series are listed on the AnTech Nova page.
How is flow verified on analogue and Lara models?
Menu-based capacity calibration is not listed among the catalogue features of the Nova A, Lara, Optima and Nano models. On these pumps the actual flow rate is measured in the same way, with a graduated container; the adjustment knob, or the setting on the display of digital Lara models, is corrected according to this measurement.
How Are pH and ORP Electrodes Calibrated?
pH and ORP electrodes are calibrated by immersing them in buffer or calibration solutions of known value. The AnTech catalogue lists pH 4, pH 7 and pH 10 calibration solutions, and 225 mV and 475 mV ORP calibration solutions. P-coded (pH) and R-coded (ORP) electrode sets with holders come with a calibration solution.
The AnTech Lara PR 5 L/h 7 Bar pH/ORP Controlled Dosing Pump performs fully digital automatic calibration with buffer solutions; on the Nova DMPR, sensor calibration is done from the pump menu. General procedure:
- The electrode is removed from the line or its holder and rinsed with clean water; if its surface is dirty, it is cleaned.
- The electrode is immersed in the first calibration solution; once the value is stable, it is confirmed from the menu.
- The electrode is rinsed, immersed in the second solution and the process is repeated.
- The electrode is refitted, and the housing or holder is checked to make sure no air bubbles remain.
- The value measured by the pump is compared with a test kit or a portable meter.
The number of calibration points and the solutions to be used are determined by the model’s manual. Used calibration solution is not poured back into the bottle. A pH electrode must not be left dry. Because the ORP value is also affected by pH, keeping pH stable is recommended in systems where chlorine is dosed by ORP; models for pH control are on our pH dosing pump page.
On the Lara PR, a measurement settling time of 0–60 minutes can be entered for start-up. When the pump is first switched on after calibration, this time allows the electrode to stabilise and prevents overdosing based on a false reading. All measurement-controlled models are in the pH / ORP controlled dosing pumps category.
How Is a Free Chlorine Sensor Calibrated?
A free chlorine sensor is calibrated against a reference measurement made with the DPD method on a sample taken from the water the sensor is measuring. The Nova DMİA measures free chlorine with an amperometric sensor, and sensor calibration is done from the pump menu. The catalogue lists 0–2 ppm and 0–5 ppm selective free chlorine sensors and a 0–10 ppm amperometric cell for the Nova DMİA; the sensor and its housing are not supplied with the pump.
- The sensor stabilises while running in its housing under normal flow conditions.
- A water sample is taken from the point where the sensor is located, and free chlorine is measured with a photometer or test kit using DPD reagent.
- The measured value is entered into the menu as the reference.
- After a while, the reference measurement is repeated to check whether the sensor is holding the value.
Amperometric sensor readings can be affected by flow, temperature and the pH of the water. Calibration is therefore carried out under the system’s normal operating conditions. The Nova DMİA also has a PT100 temperature sensor input. Models with free chlorine measurement are listed in the dosing pumps with chlorine measurement category.
When Is Calibration Needed?
Calibration is needed at initial commissioning and after any change that affects dosing or measurement. The table below shows which calibration to carry out in which situation.
| Situation | Capacity calibration | Sensor calibration |
|---|---|---|
| Initial commissioning | Yes | Yes (on measurement-controlled models) |
| Line pressure or injection point has changed | Yes | — |
| Head, check valve, suction/discharge assembly or hose replaced | Yes | — |
| Type or concentration of the chemical has changed | Yes | — |
| Electrode or sensor replaced or cleaned | — | Yes |
| Value on the display does not match the test kit | — | Yes |
| Daily chemical consumption does not match the flow rate on the display | Yes | — |
| Restarting after a long shutdown | Check | Check |
Beyond these situations, the periodic check interval depends on water quality and usage. Calibration is usually carried out together with maintenance or part replacement; details are on our dosing pump maintenance service and dosing pump part replacement pages. The first calibration of a new pump is carried out during dosing pump installation.
Sources
- AnTech 2025 Product Catalogue (KT_25 R02): feature lists for the Nova D, Nova DMPR, Nova DMİA and Lara PR, flow–pressure values for the Nova 10 L/h, calibration solutions and electrode sets with holders.
Frequently Asked Questions
Why is AnTech dosing pump calibration necessary?
The flow rate of an electromagnetic pump changes with line pressure; the Nova 10 L/h model delivers 10 L/h at 10 bar and 20 L/h at 2 bar. Capacity calibration matches the flow rate on the display to the actual flow rate in your line. On measurement-controlled models, sensor calibration additionally keeps the measurement, and therefore the dosing, accurate.
Which solutions are used to calibrate a pH electrode?
It is calibrated with pH buffer solutions of known value. The AnTech catalogue lists pH 4, pH 7 and pH 10 solutions. Which solutions to use and how many calibration points to take are determined by the pump's manual.
How is a chlorine sensor calibrated?
Once the sensor has stabilised under normal flow conditions, a sample is taken from the water it is measuring and free chlorine is measured by the DPD method. This value is entered into the pump menu as the reference. Some time after calibration, the measurement is repeated to check the result.
Can analogue pumps be calibrated?
Analogue models do not have menu-based capacity calibration, but the actual flow rate can be measured with a graduated container. The adjustment knob is corrected according to this measurement, and the chlorine level in the water is checked with a test kit.
How often should calibration be repeated?
There is no fixed interval; it depends on water quality, the chemical and usage. Calibration should be checked when the value on the display does not match the test kit or daily consumption, when a part or electrode is replaced, and after long shutdowns.