Baldor 22H series Installation & Operating Manual page 23

Section 1
General Information
Table 3-7 Output Current Derating at Reduced Input Voltages (2.5KHz PWM)
Input Voltage
230VAC Control
180VAC
190VAC
208VAC
230VAC
240VAC
3-12 Receiving & Installation
Single Phase Operation
Single phase operation is not possible for Series 22H Line Regen Vector Controls.
Operating the Control at a Reduced Input Voltage
Series 22H Controls use a DC Bus regulation technique that provides full output voltage
(240VAC for 230VAC Controls; or 480VAC for 460VAC controls) for the full input voltage
range. However, at reduced input voltages the output current of the control may have to
be derated. Table 3-7 lists the % derating of the output current for various motor voltage
ratings and input power voltage levels to the control.
460VAC Control 240/480VAC Motor
340VAC
360VAC
400VAC
440VAC
480VAC
For example:
A 460VAC Control that has a 400VAC input line can provide 90% of the rated current to a
480VAC motor. In the Section 6 specifications we find our example 10HP control is
ZD22H410-EL has a continuous current rating of 15 Amps. The derated current can be
calculated as follows: 15A x 90% = 13.5A derated value.
% of Output Current after Derating
230/440VAC Motor
77% 84%
82% 89%
90% 99%
100% 100%
100% 100%
208/400VAC Motor
93%
98%
100%
100%
100%
MN722