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Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings)

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Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings)

Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings)
Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings) Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings) Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings) Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings) Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings) Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings)

Large Image :  Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings) Get Best Price

Product Details:
Place of Origin: DE
Brand Name: Endress+Hauser
Certification: ATEX
Model Number: COY31-Z
Document: ACH-AB-P+F-E+H-IFM-ASCO-YOK...WA.pdf
Payment & Shipping Terms:
Minimum Order Quantity: 1
Price: Negotiable
Packaging Details: carton
Delivery Time: Negotiable
Payment Terms: T/T,XT,ALIPAY
Supply Ability: 100pcs per month
Contact Now
Detailed Product Description
Power Supply: 1 Ambient Temperature: -
Electrical Rating: G Certifications: S
Highlight:

Endress+Hauser COY31-Z DO sensor maintenance kit

,

COS31 COS41 dissolved oxygen sensor membrane

,

DO sensor electrolyte and O-rings replacement

Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings)

Endress+Hauser COY31-Z (51506784) service kit for Oxymax COS31 & COS41 dissolved oxygen sensors. Includes membrane caps, KCl electrolyte, sealing rings & polishing strips.

Product Overview

The Endress+Hauser COY31-Z​ (Article No. 51506784) is the standard maintenance/spare parts kit​ for Oxymax W COS31​ (3-electrode) and COS41​ (2-electrode) amperometric dissolved oxygen sensors. It contains all consumables required for periodic membrane replacement and electrolyte refill — including COY31-WP membrane caps, COY3-F potassium chloride (KCl) electrolyte solution, Viton O-ring seals (COY31-OR), and cathode polishing strips (COY3-PF)​ — ensuring continued measurement accuracy in wastewater aeration and water quality monitoring.

Technical Specifications (Kit Contents)

Parameter

Specification

Model / Order Code​

COY31-Z​

E+H Article Number​

51506784​

Compatible Sensors​

Oxymax W COS31, Oxymax W COS41​

Included Membrane Cap​

COY31-WP​ (Standard Response, POM)

Electrolyte​

COY3-F​ – KCl Solution (Saturated)

Sealing Rings​

COY31-OR​ (Viton / FKM)

Cathode Polish Strips​

COY3-PF​ (Emery Paper)

Pack Qty (Membrane Caps)​

Typically 2 pcs

Technical Specifications (Application & Conditions)

Parameter

Specification

Product Type​

Consumables / Service Kit

Sensor Type​

Amperometric Galvanic / Clark-type DO Sensor

Application Area​

Wastewater, Surface Water, Aquaculture

Recommended Service Interval​

3–6 months (process dependent)

Fast-Response Variant Kit​

COY31-S-Z​ (separate item, for COS31-S)

Key Features

  • Complete Service Package:​ Bundles membrane, electrolyte, seals, and polish strips — no separate sourcing needed.

  • Genuine OEM Match:​ Ensures chemical compatibility and measurement traceability with COS31/COS41 sensors.

  • Standard vs. Fast Response:​ This kit (COY31-Z) fits standard-response sensors; fast-response COS31-S requires COY31-S-Z.

  • Extended Sensor Life:​ Regular membrane/electrolyte renewal restores sensor performance and avoids premature sensor replacement.

Applications

  • Wastewater Aeration Basins:​ Routine servicing of DO probes in activated sludge process control.

  • Environmental Monitoring:​ Maintenance of sensors deployed in rivers, lakes, or coastal waters.

  • Aquaculture:​ Keeping DO probes in fish tanks and raceways within spec.

  • Industrial Effluent:​ Scheduled preventive maintenance in discharge monitoring stations.

Note: Membrane cap COY31-WP is also available separately (Order No. typically 51506684). Always verify sensor model (COS31/COS41) and response type before ordering.

Endress+Hauser COY31-Z | COS31/COS41 DO Sensor Maintenance Kit (Membrane, Electrolyte, O-rings) 0

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About ACH

Founded in 2012, ACH is a top-tier distributor of industrial automation products, supplying genuine devices from leading brands like ABB, P+F, E&H, AB, MTL  to emerging markets worldwide. Our mission is to provide 100% Genuine products at the most competitive prices, helping customers reduce costs and strengthen their market position.

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Frequently Ask & Questions
Are preferential prices available?

Long-term brand partners can get competitive product prices. At the same time, ACH controls the profit per order to 5%, providing the most competitive prices.

Are the Products Genuine OEM Units?

Yes, all products from ACH are certified genuine OEM units. We acquire our inventory through official OEM channels and trusted third-party suppliers, ensuring every item is authentic and reliable.

How will you arrange shipment?

We'll handle the shipping for you. Through our partnerships, we can secure competitive rates with major carriers like FedEx, DHL, TNT, and UPS, ensuring a smooth and cost-effective delivery.

What is the warranty of goods?

One-year Warranty.

How long is the logistics cycle of the product?

Products are divided into spot and futures, and the delivery period of different brands of products is also different. For details, please contact the ACH business manager.

Ratings & Review

Overall Rating

5.0
Based on 50 reviews for this supplier

Rating Snapshot

The following is the distribution of all ratings
5 stars
100%
4 stars
0%
3 stars
0%
2 stars
0%
1 stars
0%

All Reviews

K
Khalid Al Mansouri
United Arab Emirates May 24.2026
Helpful (1)
Excellent quality, fast delivery, works flawlessly!
S
Siti Aisyah
Indonesia May 22.2026
Helpful (1)
Reliable, accurate, works great for industrial use!
O
Omar Farooq
Pakistan May 13.2026
Helpful (1)
Accurate readings, fast delivery, very reliable!
Tag:

e&h instruments,

e and h flow meter,

e&h flow meter

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