Water Pump Failures: Top Weak Point is the Cable

14 October 2021

When the decision for a new dewatering pump is pending, the models are often meticulously compared. However, users quickly overlook the fact that the success of the drainage system depends to a large extent on the cable used. 
 
What many people do not know, but repair statistics prove: a defective power cable is the most frequent cause of pump failure. 
 
The pump manufacturer Tsurumi points this out. After all, the cable is the first link in the failure chain and therefore the most important element to consider first. 
 
A closer look reveals various causes of failure, such as improper use. Probably everywhere in business there are occasional time bottlenecks. But when things must be done quickly, the manufacturer's specifications are not always followed.  

The expert at Tsurumi´s EU headquarters in Düsseldorf, Germany, knows all the damage patterns. He points to handle and eyebolts, which are on the pumps for a good reason - only here point loads are permitted. 
 
Usually, heavy vehicles run over the cable lying on stony ground, or the cable is overlooked when unloading building materials and equipment. That is why the grade and quality of the cable is so relevant. Rubber hose cables, for example according to the specification H07RN-F, are common on the market. These are allowed, but only fulfil the basic requirements. 
 
In a direct comparison, technical aspects such as the structure of the stranded wire, the material of the core insulation, the outer sheath and (if available) the inner sheath, the maximum voltages and current carrying capacities, the bending radius and the temperature range in which the cable can maintain the assured properties are relevant. 
 
For its own 400V pumps, Tsurumi uses higher quality cables. The NSSHÖU cable is a mechanically robust rubber cable that is intended for the heavy use in mines and quarries. But experience shows that the limits of physics are quickly reached even in "normal" civil engineering projects. 
 
The manufacturer has therefore made these cables the standard for many pumps in its huge range. Tsurumi delivers - mostly immediately from stock - more than 500 models with maximum flow rates of up to 30m3/min or 216 m maximum head. 

Courtesy of Tsurumi.