How is the electrolyte for a liquid-resistance starting cabinet prepared?
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I have a 1250KW 10kv liquid resistance starting cabinet that keeps tripping during startup – either due to overcurrent or when the transition after startup is completed Seeking help from fellow sailors?
Find out why a trip occurs during the conversion process – is the movement of the plates normal? Is the timing appropriate? If there is overcurrent during conversion, it may be due to high resistance in the electrolyte; in that case, some resistive powder needs to be added
Does your high-voltage relay protection use traditional relay types, or modern integrated protection devices? If it is an old-style relay protection, it needs to be adjusted accordingly. There may be an issue with the parameter settings of the comprehensive protection device. Next, check the main circuit wiring. Finally, it’s possible that the water resistance is too low, resulting in a prolonged startup time.
Startup time: 27 seconds. The protection devices of Shanghai Dongfang Electronics are not of the old type; control is carried out using PLCs. I suspect that the ratio of my liquids is incorrect. Can anyone give me some advice? The water resistance cabinet uses components from the former Wanzhou Electrical Appliance Company in Xiangfan, Hubei. Is there a calculation method for liquid formulations?
Reply to 4# pang*nghua: Calculation of the electrolyte ratio in a water resistance cabinet: R (resistance of the water resistance cabinet) = P (rated power of the motor) times 1000 / (2.5–3.5) times the starting current multiplier times 1.732 times I (rated current of the motor); the larger the motor, the smaller the value of the starting current multiplier.
Measurement method: A crane lighting transformer with a secondary voltage of around 36V is connected in series between the input and output terminals of one phase in the water resistance cabinet; the primary side of this transformer is supplied with a 380V power source. By measuring the current of a certain phase in the water resistance cabinet, the resistance value can be calculated. High resistance – add chemical dosage ； If the resistance is low, add water. Until the requirements are met.
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