The choice of the motor is influenced by the way the fire fan is operated, which can be used in normal operation for HVAC applications and in case of fire for smoke and flue gas extraction:
Operation only in times of fire
The electrical power supply, supply cabling and fan location is designed and implemented in such a way that the use of solid-state standby power supplies is not required, fans are powered e.g. from independent plant transformer stations, separate outlets from several directions, motor-generator etc. Flow control by Y/D switching is not required. In this case, the standard supplied motors marked as 400 V (alternatively also 230/400 V) can be used. Thermal winding protectors must be discarded.
Operation for normal HVAC applications and fire ventilation
For normal HVAC operation, Y/D switched flow control is required. The electrical power supply, supply cabling and fan location is designed and implemented in such a way that the use of solid-state standby power supplies is not required; the fans are powered, e.g., from independent plant transformer stations, separate outlets from multiple directions, motor-generator, etc. In this case, standard supplied motors designated as 400 V switchable Y/D can be used. In the event of a fire, the thermal protections in the windings must be bridged in a safe manner.
Use for normal HVAC and fire ventilation, inverter supply
Electric power supply requires the use of solid-state switching power supplies (inverters).
- If the inverter has a 3x400V AC output, the motors supplied by us as standard must be marked as 400V and the thermal protectors in the windings must be safely bridged in the event of a fire. The use of the inverter must be specified in the order and a version suitable for the inverter will be supplied by the manufacturer.
- If the inverter has an AC 3x230 V output, motors marked as 230/400 V must be used, supplied by us on special order, and in case of fire, the thermal protections in the windings must be bridged in a safe manner. The use of the inverter must be specified in the order and a version suitable for the inverter will be supplied by the manufacturer.
General information about motors
The fans we supply are equipped with three-phase motors marked in the operating voltage data in one of the two following ways (data applies only to operation in power networks with a combined voltage of 400V (380 to 415V)).
The 230/400 V indication means that the motor can only be operated with the windings connected in a star (a triangular connection will destroy the motor).
The 400 V indication means that the motor can be operated with the windings connected in a triangle (if the manufacturer recommends Y/D switching in the instructions, the fan can be operated permanently at low or high speed). If it is not recommended by the manufacturer for control, it can only be operated in a triangular connection. A switchable 400V winding (Y/D) is advantageous for inexpensive fan speed control and thus fan flow.
Attention!
If you require the fan to be operated with electronic converters, this must be specified in the order. The motors are subjected to considerable stress by the inverters and therefore require a special insulation design. When powered by inverters, the magnetic circuits, windings and insulation are stressed by high amplitudes of higher harmonic frequencies, which are the product of pulse-width modulation of the output voltage in inverters.