Toshiba VF010H05 用户手册

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RTD Input: Will bias the register in either direction based on real-time input of 

the motor, bearing and even ambient temperature conditions.

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Dynamic Reset is another feature that adds reliability and consistency to the 

performance of the soft starter. If a motor overload condition occurs and the soft 

starter trips, it cannot be reset until sufficient cool down time has elapsed. This 

cool down time is determined by the thermal state of the motor when it tripped 

(i.e. hot motors cool more quickly due to additional convection). The cool down 

time is also biased by RTD measurements when used.

 

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Retentive Memory provides continuous overload protection and real time 

         reset even if power is lost. Upon restoration of  power, the soft starter will 

         read the Real Time Clock and restore the thermal register to what it should be 

         given the elapsed time.

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Learned Reset Capacity is a feature that is unique to the JKSSS+ Series. By 

sampling the amount of thermal capacity used in the previous three successful 

starts, the soft starter will not allow a reset until a sufficient amount of thermal 

capacity has been regained in the motor. This prevents nuisance tripping and 

insures that unsuccessful start attempts (which would otherwise use up the 

starts-per-hour capacity of the motor) are not counted. 

 

The SCR gate firing circuit is critical to performance and stability of the system. 

The firing circuit includes several unique features which enhance the ruggedness, 

noise immunity and flexibility for maximized performance.  In most applications, this 

performance is attained without the need for reactors or field installed devices. These 

features include:

 Auto Synchronizing of the gate timing pulses match each phase firing angle 

to their respective phases. The starter actively tracks minor shifts in the line fre-

quency, avoiding nuisance tripping that may happen with conventional gate firing 

systems. This is especially useful on portable or backup generator supplies, 

allowing the starter to be used confidently in applications that have unstable 

power

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 Sustained Pulse firing keeps the firing signal active for 270 electrical degrees, 

ensuring that the DC gate pulse causes the SCR to fire even if line noise is 

present at a critical moment. This provides the soft starter with superior noise 

immunity and protects against misfiring, enhancing the system reliability.

 Closed Loop Firing Control is a method of balancing the SCR firing pattern 

based on the desired output. The CPU uses feedback signals from both the 

output current and voltage providing smooth output and preventing imbalances 

during ramping which prevents unnecessary motor heating

 Transformer Isolation of the firing signals prevents interference from line noise 

and EMI/RFI signals that may be present. Specially designed 120V 3 phase iso-

lation transformers provide potential measurement, firing board power and gate 

power systems while being isolated from the line voltage. High isolation Ring 

Transformers are used to step this down to 28Vac for the Sustained Pulse firing 

circuit, providing further isolation for the SCR gates.

 Fiber Optic Isolation is provided for all signal interfaces between the Medium 

Voltage and Low Voltage systems. Even the current signals from CTs are con-

verted to fiber optic signals for maximum isolation and safety.