Multi-parameter Instruments: Solutions and spare parts
Components in contact with the measured medium always wear out to a greater or lesser extent. Long-term accurate and reliable measurement therefore requires maintenance. Depending on the type of sensors used, this mainly involves regular calibrations, replacement of worn parts, or entire sensors (where applicable).
You can easily handle a number of these common tasks yourself, saving time and costs. You can find the relevant procedures in the user's manual of the individual products, or we can also advise you over the phone. Below you will find the necessary materials.
Membrane heads for CSOT, CSCT, CSUT, CSDT, CSZT sensors
Membrane heads of all INSA sensors are easily replaceable. By timely replacement of the worn membrane, the service life of the mentioned sensors can be extended almost indefinitely, if the damage of the previous membrane did not lead to contamination of the sensor's internal system. Membrane heads for amperometric sensors (types MH11 xx for series 43 sensors) must be filled with the corresponding electrolyte prior to assembly. Optical sensor heads (type MH21 for CSOT53 and CSOT63 series sensors) are mounted dry.
A cost-effective alternative to buying a new membrane head is the option of used head repair in our facility.
| Type | Suitable for | Front protective elements |
| MH11 O2 | CSOT43PS, CSOT43PL, CSOT43LPS | No |
| MH11 O2L | CSOT43LS, CSOT43LL, CSOT43LZ | Yes |
| MH11 C2 | CSCT43 | No |
| MH11 U2 | CSUT43 | No |
| MH11 D2 | CSDT43 | No |
| MH11 Z2 | CSZT43 | No |
| MH21 O2 | CSOT53, CSOT63 | No |
Electrolyte for CSOT43, CSCT43, CSUT43, CSDT43, CSZT43 sensors
Electrolyte is used to fill membrane heads for INSA amperometric sensors. The packaging differs (bottle, syringe) according to the consistency and usage of the individual variants.
| Type | Suitable for sensors | Packaging |
| ES43 O2 | CSOT43 | Bottle 10 ml, 20 ml |
| ES43 C2 | CSCT43 | Bottle 20 ml |
| ES43 U2 | CSUT43 | Syringe 2 ml |
| ES43 D2 | CSDT43 | Bottle 20 ml |
| ES43 Z2 | CSZT43 | Bottle 20 ml |
pH buffers
Buffers are used for calibration of pH sensors. The IEC (NBS) buffer set pH 4.01 - 6.87 - 9.18 is suitable for basic measurement range. Buffers are supplied in bottle sets 3 x 100 ml, 3 x 500 ml or 3 x 1000 ml, or as separate bottles.
| Recommended set | Other available buffers | |
| pH 1.68 ± 0.05 | pH 3.56 ± 0.05 | |
| pH 4.01 ± 0.02 | pH 6.00 ± 0.05 | |
| pH 6.87 ± 0.02 | pH 7.00 ± 0.02 | pH 7.41 ± 0.02 |
| pH 9.18 ± 0.02 | pH 10.01 ± 0.05 | pH 10.90 ± 0.05 |
| pH 11.88 ± 0.05 | pH 12.83 ± 0.05 | |
Buffers pH 3.56 4.01 6.87 7.41 9.18 are primary IEC (NBS) buffers, 1.68 is primary IEC (NBS) standard for low pH range, 10.01 is supplementary IEC (NBS) standard, 6.00 7.00 10.01 10.90 11.88 12.83 are standardized against IEC using a glass pH electrode. The listed values are valid at 25 °C.
ORP reference solution
The reference solution is used to calibrate ORP sensors. The listed ORP value is valid at 25 °C, with the Ag/AgCl reference electrode.
| Product code | Value | Bottle sizes |
| SS ORP 11 | 225 mV | 100 ml, 500 ml, 1000 ml |
| SS ORP 12 | 252 mV | 100 ml, 500 ml, 1000 ml |
| SS ORP 13 | 468 mV | 100 ml, 500 ml, 1000 ml |
Conductivity calibration solutions
Solutions of the SS ES 11 series are used for calibration of conductivity sensors. They are supplied in 100 ml, 500 ml or 1000 ml bottles.
| Value at 20 °C | Value at 25 °C |
| 133 μS/cm | 147 μS/cm |
| 1278 μS/cm | 1413 μS/cm |
| 11.67 mS/cm | 12.88 mS/cm |
| 102.1 mS/cm | 111.8 mS/cm |
These are KCl solutions.
Calibration solutions for ISE measurement
We can supply calibration solutions for ISE measurements on your request. These are usually packaged in 100 ml, 500 ml or 1000 ml bottles.
- Ammonium, NH4Cl
- Lithium, LiCl
- Sodium, NaCl
- Potassium, KCl
- Calcium, CaCl2
- Barium, BaCl2
- Nitrate, KNO3
- Fluoroborate, NaBF4
- Perchlorate, NaClO4
- Fluoride, NaF
- Chloride, NaCl
- Ammonia, NH4Cl
- Carbonate, NaHCO3
Auxiliary solutions for pH, ORP and ISE sensors
We can also supply further auxiliary solutions, useful for maintenance of pH and ORP sensors, or for ISE measurements:
- Deproteining solution for cleaning pH sensors
- Non-ionic detergent for cleaning pH sensors
- Storage solution for pH and ORP sensors
- Reference solutions and salt bridge solutions
- Conditioning solutions, Ionic Strength Adjustors for ISE measurements