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• The VariMax50 NG is part of a new range of control units that, with the necessary
additional functions, are suitable for the optimum control of rotary heat exchangers.
The series comes in two sizes, the VariMax25 NG and VariMax50 NG.
Both the control units operate 3-phase stepper motors.
The control units have a 0-10 V input signal.
• The VariMax50 NG is intended for rotors up to 2500 mm with a max rotor speed of
12 rpm. If the rotor requires a higher rotor speed, rotor diameter should be reduced.
• The VariMax50 NG has internal Modbus functions.
For more information, see the manual on our website, www.ibccontrol.se
• The VariMax50 NG has an integrated input signal offset, which means rotor efficiency is
proportional to the input signal.
• The VariMax50 NG threshold is set at 0.1 V (hysteresis 0.13 - 0.07 V). If the input signal
drops below this value, the rotor will stop.
•
The VariMax50 NG has an internal rotation monitor. The rotation monitor is patent
pending.
This is activated when the DIP switch for the “External rotation monitor” is in the OFF
position.
The internal rotation monitor performs measurements at different times, depending on
whether the speed of the motor is above or below 37 rpm.
At a motor speed above 37 rpm, the measurement begins when the speed is stable,
normally starting after about 30 seconds, after which measurements are carried out
continually. The yellow “Rotation” LED flashes after each completed, approved
measurement. The time between the measurements varies from 22 seconds to nearly two
minutes.
At a motor speed below 37 rpm, the control unit will increase the speed to 37 rpm at
two-hour intervals. At start-up, this measurement will start after 10 minutes.
The speed will remain steady for 2 minutes, while the actual measurement is being
performed. To verify the measurement, an additional measurement is conducted
10 minutes later. If both of these measurements are positive, i.e. everything is normal,
the next measurement will not take place until two hours later.
This sequence is then repeated with the same time intervals, provided the motor speed is
below 37 rpm.
DESCRIPTION OF FUNCTIONS
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Содержание VariMax50
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