Revision 1.1
Variphase User Manual
Page 3
Product Overview
AirCare
Variphase
™ controls combine intelligent speed control with industry standard MODBUS
networking. The versatile design allows for either analog (0-5V or 20mA loop) or network speed
control.
In network mode, each VariPhase™ unit is assigned a unique address. By linking Variphases
together with networking cables, a Zone of up to 125 units can be built. Each unit can then be
precisely controlled from a single AirCare Console™. Consoles models support up to 4 zones, or
500 Variphases in total.
For optimal efficiency and reduced acoustic noise, Variphase models include intelligent Auxiliary
winding control using a 3
rd
wire to the motor. Permanent Split Capacitor (PSC) motor loads can
be connected in three-wire mode, or wired conventionally for standard operation.
Variphase’s closed-loop control capability supports a wide range of sensors including air-pressure,
temperature and tachometers. In closed-loop mode, Variphase precisely adjusts motor speed
using a PID loop to maintain a set-point.
Installing a distributed network of AirCare controls is simplified by flexible wiring options and
diagnostic LEDs. AirCare can also be controlled from an analog signal source.
Variphases come in three form factors, depending on their current rating. Variphases rated at
less than 2 amps are supplied as a board only and require 4 standoffs for mounting. From 3-6
amps, controls are supplied with a standard aluminum L-bracket that also serves as a heatsink.
16 amp Variphase’s incorporate an extruded aluminum heatsink for robust thermal management.
Optional covers provide NEMA1 level protection for all ratings.
Variphase HP has four sets of power terminals to simplify connection to up to four motors. In this
configuration all four motors will be supplied with the same voltage and run at the same speed.
Variphase is a robust variable-voltage motor speed control. Internal algorithms precisely control
motor voltage resulting in a wide speed range (typically 20-100%).
