lev-co 13-12, User Manual

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1.3.1 Model 13-12 – Type 1 – VFD as a Contactor Replacement
In this architecture, the VFD operates simply as an enhanced-performance contactor replacement. The
benefits are the ability to gently ramp motor speed up and down at start and stop, thereby minimizing
motor stresses and extending motor life, as well as eliminating heavy startup surge currents and their
attendant wasteful energy costs. Motor speed may also be adjusted via a supplied speed adjustment
potentiometer to obtain desired extraction performance, reduce noise, or to deliberately reduce energy
consumption during periods when peak demand charges are in effect.
External start/stop interlocking is provided to permit control by one or more external contacts, such as
damper limit switches, foot switches, hood switches, or current-sensing switches. AMU (air make-up
unit) interlocking is also available via this function.
An indicator is provided to show when the motor is running. Options include fused disconnect and duct
pressure indicator.
Figure 1 – Type 1 Architecture