Reference information, Detailed drive operation, Accel/decel time – Rockwell Automation 20A PowerFlex 70EC/700VC User Manual
Page 7: Alarms, Accel/decel time alarms
Reference Information
Detailed Drive Operation
This chapter explains PowerFlex drive functions in detail. Explanations are
organized alphabetically by topic. Refer to the Table of Contents for a listing of
topics.
Accel/Decel Time
[Accel Time 1, 2]
[Decel Time 1, 2]
The Accel Time parameters set the rate at which the drive ramps its output
frequency after a Start or Stop command or during a change in command frequency
(speed change). The rate established is the result of the programmed Accel or
Decel Time and the Maximum Frequency.
Two accel and decel times exist to allow the user to change rates “on the fly” via
PLC command or digital input. Times are adjustable in 0.1 second increments from
0.0 seconds to 3600.0 seconds.
In its factory default condition, the secondary accel/decel times are not active if the
related digital input functions or network commands have not been invoked.
Alarms
Alarms are indications of situations that are occurring within the drive or
application that should be annunciated to the user. These situations may affect the
drive operation or application performance. Conditions such as Power Loss or
Analog input signal loss can be detected and displayed for drive or operator action.
There are two types of alarms:
•
Type 1 Alarms are conditions that by themselves, do not cause the drive to
“trip” or shut down, but they may be an indication that, if the condition persists,
it may lead to a drive fault.
•
Type 2 Alarms are conditions that are caused by improper programming and
they prevent the drive from Starting until programming is corrected. An
example of a Type 2 alarm is when a “Start” function is assigned to a digital
input without a “Stop” function also assigned to a digital input.
Alarm Status Indication
[Drive Alarm 1]
[Drive Alarm 2]
Drive Alarm 1 is 16 bit parameter with each bit representing a specific Type 1
Alarm. Drive Alarm 2 is 16 bit parameter with each bit representing a specific Type
2 Alarm. For each Drive Alarm bit, 0 = alarm not active and 1 = alarm active.
70EC
700VC
700H
✔ ✔
Maximum Speed
Accel Time
------------------------------------
Accel Rate (Hz/sec.)
=
Maximum Speed
Decel Time
------------------------------------
Decel Rate (Hz/sec.)
=
70EC
700VC
700H
✔ ✔