IM483H/IM805H Rev. R032206
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IM483H/IM805H Rev. R032206
R e d u c i n g / D i s a b l i n g t h e O u t p u t C u r r e n t
The IM483H/IM805H will automatically reduce the current in the motor
windings after a move provided the onboard 1mA current source, along with
a current adjustment resistor, is used to set the output current and a resistor is
placed between pins 2 and 3 of connector P1. Using this will greatly reduce the
amount of motor and drive heating in your system.
The amount of current reduced will depend upon the value of the Reduction
Adjust Resistor (R
Red
) and the value of the current adjust resistor (R
Adj
) . The
Current will be reduced 0.5 seconds after the rising edge of the last Step Clock
Pulse. The value of R
Red
is calculated as follows:
I
Run
is the desired peak running
current. Range 0.4A to 4A Peak
I
Hold
is the desired peak holding
current. Range 0.2A to 4A Peak
I
Run
x I
Hold
R
Red
= 500 x
(
I
Run
- I
Hold
)
IM483H
I
Run
is the desired peak running
current. Range 1.0A to 7A Peak
I
Hold
is the desired holding cur-
rent. Range 0.5A to 7A Peak
I
Run
x I
Hold
R
Red
= 150 x
(
I
Run
- I
Hold
)
IM805H
Bottom View
CURRENT REFERENCE
CURRENT ADJUST
CURRENT REDUCTION
CURRENT ADJUST
RESISTOR
CURRENT
REDUCTION
ADJUST
RESISTOR
POWER GROUND
Pin 1
Pin 1
P1
P2
Figure 7.4: Current Reduction Adjustment Resistor Connection
