Does ZIRKON® DIS / ZIRKON® ONE DIS Need a Zero-Point Calibration?

In most applications, no. ZIRKON® DIS / ZIRKON® ONE DIS measurements are typically zero-point stable and usually require only a one-point reference calibration.

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When Is Zero-Point Calibration Not Recommended?

In normal free chlorine applications, zero-point calibration is usually unnecessary and may cause problems with measured values or reference calibration.

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Why Can Zero-Point Calibration Cause Problems?

If a zero deviation is caused by disinfectant-consuming substances, zero-point calibration can distort the measurement. In this case, the measuring point should be moved to a location where the consumption reaction is complete.

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If Zero-Point Calibration Is Performed

• Use disinfectant-free water that matches process water in all other relevant conditions.
• Do not remove disinfectant chemically just to create a zero point, as this can change water chemistry.
• After zero-point calibration, always perform a reference calibration.

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If Issues Occur After Zero-Point Calibration

Neon®/Krypton® systems:

1. Disconnect the sensor cable.
2. Wait until the measuring signal drops to 0 mV.
3. Repeat the zero-point calibration.
4. Perform a new reference calibration.

NEON® ONE / KRYPTON® ONE:

1. Reset calibration to factory setting.
2. Perform a new calibration.

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Warning: Incorrect zero-point calibration can seriously affect measurement quality.