KRIWAN pump protection relay in the inlet pumping station

2024-05-08 Products, Water and wastewater industry

Minimizing failures and optimizing the performance of the inlet pumping station are the main reasons for using KRIWAN  protection relays. Especially in an Ex-zone, temperature monitoring is crucial for operational safety.

Unser Alleskönner: INT69 PYF Premium Pumpenschutz


The wastewater treatment plant operators faced recurring challenges. In the inlet pumping station, there were three wastewater submersible motor pumps, which frequently experienced malfunctions. The explosion-proof pumps all had a PTC (Positive Temperature Coefficient) and a leakage electrode in the oil chamber, each monitored by a relay in the control cabinet. 
Particularly during the startup moment of the frequency converters, there were frequent shutdowns of the leakage relay, leading to unplanned interventions by service personnel. The long cable lengths without shielding exacerbated interference during leakage measurement.



INT69 EXF2 Diagnose BASIC EX

The existing two relays, each for monitoring the motor temperature and leakage of each pump, were replaced by the KRIWAN pump protection relay INT69 EXF2 Diagnose. This enabled more precise and reliable monitoring of the pumps, eliminating the malfunctions. Especially, the EMC-stable leakage measurement contributed significantly to this improvement. The additional function of rotor recognition immediately revealed that the pumps exhibited the greatest interference during leakage measurement at the moment of frequency converter startup. With this information, the leakage monitoring could be adjusted specifically for the application.

The locked shutdown and ATEX approval for monitoring the motor temperature using PTC or bimetallic elements in explosion-proof pumps of the ignition protection type pressurized enclosure Ex d make the INT69 EXF2 Diagnose protection relay ideal for these applications and types of pumps.


Application Example

KRIWAN pump protection relay INT69 EXF2 diagnosis BASIC EX in inlet pumping station

To the application flyer

Do you have further questions or comments about the blog post? Please contact us!