Significant energy savings can be made through the use of frequency converters in your greenhouse heating system.

Standard transfer and circulation pump units are rated to run at a constant speed that is dimensioned to handle extreme weather conditions. Most of the year this extra power is not needed.

A frequency converter will allow you to regulate the speed of the motor - and thus the flow and pressure - quickly and exactly.

Reducing motor speed by 20% for a centrifugal pump corresponds to a 20% reduction in flow, whereas the energy consumption can be reduced by as much as 50%.

By running your pumps at reduced speed during most of the year where full capacity is not needed you can realize significant energy savings.

Johnson Pump Horticulture is a wholesaler of Danfoss frequency converters and we offer built-on or separate frequency converters. Our service is carried out by authorized engineers; also accessible through a telephone hotline service.

The built-on units (VLT FCM 300 series) are a combined frequency converter and motor drive for up to 7.5 kW with the footprint of a standard motor. The separate frequency converters (VLT HVAC Drive FC 100) can regulate standard motors of the Johnson Pump range from 1.1 kW, and can be housed separately side-by-side in a controlled environment (IP20 and IP21 versions) or wall-mounted (IP54, IP55 and IP66 versions). Both may be controlled manually or by sensor/climate computer input.

VLT FCM 300 series
for motor drives up to 7.5 kW

• Compact, footprint no larger than for standard motor
• No need for special wiring
• Pre-set adaptation between frequency converter and motor providing precise and energy efficient control
• Built-in RFI filter ensures compliance with EMC directives
• Control options via standard start/stop signals, remote potentiometer or RS 485 standard serial interface
• PID controller

See Danfoss for more details
Johnson Pump Horticulture QuickStart Guides

VLT HVAC Drive FC 100 series
for standard motor drives from 1.1 kW

• Based on new Danfoss VLT® power and control platform
• Modular design; plug-and-play options
• Automatic Motor Adaption
• Automatic Energy Optimizer
• Integrated RFI-filter in accordance with EMC directives
• Built-in serial communication
• Easy to read and use graphic Local Control Panel
• Sleep Mode and Dry Pump Detection
• 4 Built-in auto-tune PID controllers
• Advanced energy saving and monitoring functions
• Integrated service switch
• IP20, IP21, IP54, IP55 or IP66 housing
• Optional coating of electronics
• Separate compact cabinet for installation in controlled environment

See Danfoss for more details
Johnson Pump Horticulture QuickStart Guides