Output Stage; Control Module; Installation - Bosch Rexroth LTH Technical Information Manual

40/60 Bosch Rexroth AG
2 Power Unit LTH

2.4.5 Output Stage

The output stage comprises 6 IGBT transistors and 6 potential-free control circuits. The motor currents
are measured and the values are routed to the control module. The output stage switches off immediately
when short-circuits on the motor outputs occur. The temperature of the heat sink and of the motor are
monitored.

2.4.6 Control Module

The control module controls the current and the number of revolutions of the EC motor. The analog no-
minal values of the current control or of the external power tool control as well as the 2-track increment
at the transmitter of the EC motor are evaluated by the control module.
NOTE:
The control module provides the moment redundancy signal (from the motor current) and the angle red-
undancy signals ZIMP and CLK for current control. The part which is proportional to acceleration (mo-
ment of inertia) and the part which is proportional to speed (friction) are calculated.
2.5

Installation

The LTH power unit is mounted by the suspension lugs on the rear panel. The installation location is nor-
mally determined by the condition within the vicinity of the power tool systems. However, the installation
location need not be directly adjacent to the power tools.
NOTE:
Fig. 4:
When installing a power tool station with several power units and possibly external controls (e.g. SE 200)
at a central site, it must be ensured that clearances of at least 40 mm are available on all sides for air
circulation. These clearances should not be blocked by cable channels or harnesses.
CAUTION: When intense dust is generated at the installation location or the humidity is high, the power
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With the current control inserted, the nominal value signals from an external control are igno-
red, providing the current control is not programmed in the monitoring mode.
The maximum cable length between power unit and power tool must not exceed 50 m.
M4
LTH
Installation on Mounting Frame
unit must be installed in a control cabinet with protection mode IP 54. For this purpose, spe-
cial control cabinets are offered by the manufacturer.
LTH | 3 609 929 408/2.1