LATEST JAGUAR INVERTER LIFTS PERFORMANCE HIGHER
Product News
12 August 2005
IMO Precision Controls, one of the UK's leading automation and control specialists, has developed a new series of Jaguar inverters, the LE, which is aimed at giving lift applications a significant performance boost.
Of particular note is the LE's ability to be driven by battery power, thus allowing otherwise trapped lift passengers to be rescued quickly and easily in the event of mains power failure.
The LE has a unique input function that uses timers to filter any difference between BRKS and BRKE signals to check that the lift brake has actually operated. A dedicated brake control signal (BRKS) means that the LE directly controls the opening and closing of the mechanical brake without assistance from the main lift controller. The LE also contains built-in adjustable timers to delay the BRKS signal in order to match the mechanical brakes' actual opening and closing time.
Other features include a restart time function, which avoids damage from contactor racing causing harmful regenerative currents emanating from the motor, and a contactor controller which times the opening and closing of the magnetic contactor in sequence with the inverter and motor operation. Thus, start and end delay times allow contactor operation without making or breaking motor current.
In closed loop applications the LE does not need an external signal for zero speed command. This helps to avoid shock at starting and stopping due to car roll-back. Additionally, there is no need to use a lift controller with explicit zero speed command function.
In open loop applications, to avoid possible "jolts" the user can choose between start using a pre-programmed starting frequency held for a period of time, or start by holding on DC braking for a short time.
The LE includes a match timer to validate speed change commands. This function is useful for lift controllers using relays for output switching that could bounce and give false signals to the inverter drive.
The LE is available in two ranges: 0.4 -400kW, 400V, 3-phase and
0.4 - 90kW, 230V, 3-phase input.
