Motor overcurrent
Thread Content
For a 37KW soft-start centrifugal pump (used for testing new pumps, with water as the medium), when it is started with the outlet valve closed, the current exceeds 1 times the rated value and causes tripping – what could be the reasons? Is there a problem with the electrical system? (1 as primary, 1 as backup; both pumps are in the same condition)
The centrifugal pump consumes the least power when its valve is closed. The starting current during soft start is generally 2-3 times the rated current. Is there any conflict between the start-up time and your protection time?
Possible reasons: 1. The current setting of the overload protector is too low； 2. The overload protection time setting is too short ； 3. An error in the pump itself causes an increase in current ；
The starting current of soft starting is generally two to three times the normal starting current.
Variable-frequency start or star-delta start! This kind of problem shouldn’t occur with variable-frequency starting, right?
1. The startup protection time is too short; try increasing it. 2. Check whether the pump rotates normally; there may be a mechanical fault with the pump or the starting mechanism. 3. Is there a problem with the insulation?
After startup, the outlet valve does not open; after switching to the power frequency, the current remains above the rated value
After startup, the outlet valve would not open; after switching to line frequency, the current remained above the rated value, while the turning gear functioned normally
Soft start: after startup, the outlet valve does not open; once switched to the power frequency, the current remains above the rated value
Provide the flow and head model on the nameplate, measure the impeller diameter, and it can be calculated!
Are there any parameters for this pump? What is the medium used when it is actually in operation?