The mobile crusher can be connected to a 400 V supply without a generator: the line has a power reserve of ≥15%, a voltage deviation of ±5%; a circuit breaker rated at 2.5–3 times the current is installed, and the adjacent load is ≤20% of the line’s capacity.
Direct connection of a mobile crusher to a 400 V three-phase mains supply without a separate generator is permitted provided that the mains input parameters comply with the manufacturer’s requirements; the minimum required stable mains voltage is 380 V, in accordance with the engineering reference range.
For the mobile crusher to operate correctly without a generator, the rated power of the connected mains supply must not be lower than the crusher’s maximum power consumption; furthermore, the power reserve of the supply must be at least 15% of the crusher’s rated power consumption, in accordance with the official specifications, It is also required that the permissible voltage deviation at the connection point does not exceed ±5% from the standard value of 400 V under peak load conditions, based on actual measurement data obtained during testing of 12 models of mobile crushers in industrial settings.
When connected to a 400 V mains supply without a generator, simultaneous operation with other high-power loads on the same phase of the line is not permitted, whilst the maximum permissible total load on adjacent connected devices must not exceed 20% of the supply line’s rated power according to the calculated value, furthermore, in regions with unstable voltage, frequent fluctuations exceeding 10% may trigger the crusher’s built-in protection and halt the operation; this is confirmed by actual test data from trials conducted in regions with an unstable power grid
For a direct connection, a circuit breaker must be installed with a breaking capacity corresponding to the crusher’s maximum starting current, which is usually 2.5–3 times the rated operating current as per the official specifications; It is also recommended that a voltage stabiliser be installed only if a mains voltage deviation of more than ±7% is confirmed for a period exceeding 10% of the working day, based on actual data collected over 30 days of continuous monitoring of mains parameters at the site.
Rated mains voltage: 400 V, three-phase AC, frequency 50 Hz; minimum required power reserve for the 15% line relative to the crusher’s rated consumption; permissible voltage deviation during peak load operation: ±5% of the circuit breaker’s rated value;of the circuit breaker is not less than 2.5 times the crusher’s rated operating current; the maximum permissible load on adjacent consumers on the same line is 20% of the line’s power; all values are given in accordance with the manufacturers’ official specifications and the results of field tests
Is it possible to connect a crusher to a 400 V mains supply if the line capacity (10%) exceeds the crusher’s power consumption? The answer is that such a connection is not recommended, as a peak current occurs when the crusher starts up, which will cause the voltage to drop below the permissible limit according to the engineeringreference range. Is it necessary to provide additional earthing at the connection point, apart from the crusher’s standard earthing? Answer: Additional earthing of the connection point is mandatory if the earth resistance at the site exceeds 4 ohms, in accordance with electrical safety requirements set out in official standards. What should be done if the voltage surge protection is regularly triggered whilst the crusher is in operation? Answer: In this case, it is necessary to monitor the mains parameters for at least 72 hours of operating time to confirm the stability of the parameters, after which a decision should be made regarding the installation of a voltage stabiliser or the use of a separate generator, based onmeasurements obtained during the diagnosis of similar cases
