Baldor MN770 - Manual (Page 8)

Section 2
Technologies
Technologies 2-1 MN770
Overview Baldor Electric manufactures six drive types for the elevator industry. Each drive type
(Control and Motor) is best suited for a specific application.
These Series “H” Controls are:
S
15H Inverter
S
17H Vector (Encoderless)
S
18H Vector
S
19H DC SCR
S
20H DC SCR (Line Regenerative)
S
21H Inverter (Line Regenerative)
S
22H Vector (Line Regenerative)
These Baldor Series “H” controls all use the same keypad and display interface. This
makes it easy to become familiar with the programming and operation of the controls.
Set-up time of the control and motor is greatly reduced due to the automated features
“Auto-Tune” that are available within these controls.
The purpose of this section is to review each technology type to make it easier to choose
a drive for an application. Table 2-1 provides a brief overview of drive performance for
each technology type.
Table 2-1 Drive Performance Comparison
Feature DC SCR Inverter Vector
Operating speed range
(for elevators) 0 RPM to Base Speed 10% of Base Speed
to Base Speed.
0 RPM to Base Speed
Relative constant torque speed
range Wide
20:1
Narrow
5:1 - 10:1
Widest
Base Speed:1
Speed Control Yes Yes Yes
Torque Control Yes No Yes
Positioning


Yes

(Encoder or resolver feedback)
No Yes

Speed regulation:
Open Loop
Closed Loop
±
1 - 2% of base speed
±
1% of set speed
±
3% of base speed

±
1% of set speed
±
0.5 to 1% of set speed
±
0.05% of set speed
Continuous full rated torque at
zero speed No No Yes
Available peak torque 150% + 115 - 150% 150% +
Motor Brushes? Yes No No


Motion controller required for positioning.

Requires encoder or resolver feedback.
 Depends on motor size and percent slip.