Teknic CLEARPATH-EC - Underpowered DC Bus Motor Power Supplies; Switching Power Supplies; Power Supply Compliance Notes

C LEAR P ATH -EC U SER M ANUAL REV 1.11 44
U NDERPOWERED DC B US M OTOR P OWER S UPPLIES
ClearPath motors can and do work with power supplies as low as 24 volts
DC, provided that the power supply has sufficient voltage, current, and
capacitance to meet your application's motor torque and speed
requirements.
IMPORTANT: An underpowered supply can result in ClearPath
performance limitations and problems including the following:
x ClearPath is unable to complete the auto-tuning process.
The ClearPath auto-tuning feature uses aggressive moves to test
the limits of each mechanical system. A weak power supply (i.e.
one that can't handle the peak current demands required by
ClearPath) may "droop" the supply below ClearPath's minimum
operating voltage, about 21.5VDC. This can cause loss of
communication and shutdowns.
x ClearPath completes the auto-tuning process but
experiences warnings or shutdowns during
programmed motion. If Auto-Tune runs to completion, but
you experience torque saturation, voltage saturation, or both
during regular machine operation, you may be exceeding the
supply's voltage and/or current capability.
Possible remedies for underpowered DC Bus Motor Supply
x Lower the commanded acceleration and/or velocity.
Sometimes lowering commanded acceleration and/or velocity
can reduce the burden on a weaker power supply enough to
eliminate shutdowns caused by "power starvation".
x Upgrade to a more powerful supply. Look for a supply
with higher voltage, higher peak and continuous current
ratings, and a large capacitor bank.
S WITCHING P OWER S UPPLIES
Switching power supplies will work with ClearPath motors but switchers
are often not well-suited to high power servo applications
because they generally have the same peak and continuous current
ratings. This can lead the user to purchase a large but ultimately under-
worked power supply just to meet peak current requirements.
In addition, most switching supplies are not designed to manage the
regenerated energy (back-EMF) that a heavily loaded decelerating motor
returns to the power supply, especially when gravitationally loaded.
Without special provisions, regenerated energy can cause a switching
supply to reset, power cycle, shut down, or even fail.
P OWER S UPPLY C OMPLIANCE N OTES
x Any 3rd party (non-Teknic) power supply used with the
POWER4-HUB-S or PWR-STRIP-S, should be current limited or
fused to 25A or less using a 25A, >100VDC fuse.
x If UL compliance is a consideration, select a UL Listed DC fuse.
T
EKNIC , I NC . T EL . (585) 784-7454