F21025305 - IBC Control VariMax25 NG - Thermal Wheel Rotary Control Unit

• The VariMax25 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 VariMax25 NG is intended for rotors up to 1500 mm with a max rotor speed of 12 rpm. If the rotor requires a higher rotor speed, rotor diameter should be reduced.

• The VariMax25 NG has internal Modbus functions. For more information, see the manual on our website, www.ibccontrol.se

• The VariMax25 NG has an integrated input signal offset, which means rotor efficiency is proportional to the input signal.

• The VariMax25 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 VariMax25 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.

• As an alternative, the VariMax25 NG can have an external rotation monitor (magnet mounted on the rotor with an associated rotation monitor). This is connected at terminal
connections 9 and 10, and the DIP switch for the “External rotation monitor” should be in the ON position.

• If both types of rotation monitor are to be deactivated, an 820 ohm resistor (1% ¼ W) is installed between terminal connections 9 and 10.
• The VariMax25 NG has a built-in cleaning function. The function can be disconnected via DIP switches.
• VariMax25 NG only needs a shielded cable and EMC gland to the motor. Other cables do not need to be shielded or EMC glands.
• The VariMax25 NG starts automatically following a power failure, and resets all alarms upon restarting.
• The VariMax25 NG is a stepper motor with high torque throughout its speed range.
• The VariMax25 NG motor has no built-in thermal contact. The control unit regulates power and makes sure the motor will not overheat.
• A holding torque is activated when the motors is stopped, which makes sure the rotor remain static. The holding torque is lost if power to the control unit is cut.
• The motor is mounted with a 2 m cable as standard.