Rockwell powerflex 700h, Руководство по программированию

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Overview P-3
!
ATTENTION: To avoid an electric shock hazard, verify that the
voltage on the bus capacitors has discharged completely before
servicing. Check the DC bus voltage at the Power Terminal
Block by measuring between the +DC and -DC terminals,
between the +DC terminal and the chassis, and between the -DC
terminal and the chassis. The voltage must be zero for all three
measurements.
!
ATTENTION: Risk of injury or equipment damage exists. DPI
host products must not be directly connected together via 1202
cables. Unpredictable behavior can result if two or more devices
are connected in this manner.
!
ATTENTION: The sheet metal cover and mounting screws on
the ASIC Board located on the power structure are energized at
(-) DC bus potential high voltage. Risk of electrical shock, injury,
or death exists if someone comes in contact with the assembly.
!
ATTENTION: The “adjust freq” portion of the bus regulator
function is extremely useful for preventing nuisance overvoltage
faults resulting from aggressive decelerations, overhauling loads,
and eccentric loads. It forces the output frequency to be greater
than commanded frequency while the drive's bus voltage is
increasing towards levels that would otherwise cause a fault.
However, it can also cause either of the following two conditions
to occur.
1. Fast positive changes in input voltage (more than a 10%
increase within 6 minutes) can cause uncommanded positive
speed changes. However an “OverSpeed Limit” fault will
occur if the speed reaches [Max Speed] + [Overspeed Limit].
If this condition is unacceptable, action should be taken to 1)
limit supply voltages within the specification of the drive and,
2) limit fast positive input voltage changes to less than 10%.
Without taking such actions, if this operation is unacceptable,
the “adjust freq” portion of the bus regulator function must be
disabled (see parameters 161 and 162).
2. Actual deceleration times can be longer than commanded
deceleration times. However, a “Decel Inhibit” fault is
generated if the drive stops decelerating altogether. If this
condition is unacceptable, the “adjust freq” portion of the bus
regulator must be disabled (see parameters 161 and 162). In
addition, installing a properly sized dynamic brake resistor
will provide equal or better performance in most cases.
Important: These faults are not instantaneous. Test results
have shown that they can take between 2-12
seconds to occur.