JVL MAC050 User Manual page 72

3.2
3.2.19 Connecting an external power dump resistor
Connector box for power and power dump.
TT1013GB
The internal power dump can absorb up to 9W continuously and 2.5kW peak, which is
considered as appropriate for most applications.
However should a situation occur in which the connected load inertia is too large or the
deceleration too fast, the internal power dump will not be able to absorb all the returned
energy and will report the error message "regenerative overload".
In this situation the only possible solutions are as follows:
1. Decrease the acceleration/deceleration parameter.
2. Lower the attached load inertia.
3. Connect an external power resistor.
The drawing above shows how to connect an external power resistor. A wirewound
type is recommended since it will be able to absorb higher peak power than other types
of resistors.
Warnings: Ensure that the resistor value is not lower than 68 Ohm since the output can
68 JVL Industri Elektronik A/S - User Manual - Integrated Servo Motors MAC050 - 800
Power Supply
MAC800 with external power dump connection.
Note ! : Its only necessary to
L1
connect screen to signal source.
N
PE (Earth)
PE (Earth)
PD
Screen
BO
CM
Main earth.
Always make sure that
the motor is connected
to earth.
be damaged. Also avoid short-circuit of the output.
C A U TIO N
- R isk of electric
shock. D isconnect all pow er and
w ait 5 m in. before servicing
BO-PD (V)
Voltage (V)
R
Not less than
68 Ohm/100W
Wirewound
Velocity
Shielding/housing must
be connected to earth
Terminal description for the "Dump" connector.
CM = Common. Is internally connected to the ground of the DC bus.
Is only intended to be used if multiple motors share DC-bus.
BO = Bus output. The internal DC bus is connected to this terminal.
PD = Power Dump output. Behind this terminal is placed a switch
(IGBT transistor) which connect the terminal to the internal
bus ground if the voltage become higher than 400VDC.
Only MAC800
PD activated
when voltage
exceeds 400V
Time
Energy fed back from
the motor to the DC bus
400V
Nom. 325VDC
Time
Time