With
the continuous drive for process efficiency, the variable speed (frequency controlled)
models offer maximum operating savings to our customers. Most designs within
the range can be frequency controlled, duty allowing, but the variable speed
models are designed specifically to operate over the full performance curve,
without any detrimental effect on the motor or blower/exhauster output. No derating
is required. Differential pressures of 380 mbar can be achieved with flows to
600 m3/h.