Parker 690+ series User Manual

1-32 Programming Your Application
690+ Series Frequency Inverter
DYNAMIC BRAKING
Designed for all Motor Control Modes.
The dynamic braking function block
controls the rate at which energy from a
regenerating motor is dumped into a
resistive load. This dumping prevents the
dc link voltage reaching levels which
would cause an Overvoltage trip.
Functional Description
When enabled, the DYNAMIC BRAKING block monitors the internal dc link voltage every
milli-second and sets the state of the brake switch accordingly.
The dynamic braking block provides a control signal that is used by the SLEW RATE LIMIT
block. This causes the setpoint to be temporarily frozen whenever the dynamic brake is
operating because the dc link voltage exceeds the internal comparison level. This allows the stop
rate to be automatically tuned to the characteristics of the load, motor, Inverter and brake
resistor.
The DYNAMIC BRAKING block operates even when the motor output is not enabled. This
allows the block to continually monitor the energy dumped into the braking resistor, and the
energy dissipated across the brake switch. With this information the Inverter is able to deduce
the loading on the brake resistor. Optional trips may be enabled should the switch or resistor be
loaded beyond its capabilities.
The "Brake Resistor" and "Brake Switch" trips are disabled by default. To enable these trips,
refer to
TRIPS STATUS, page 1-124.
R
efer also to the Installation Product Manual, Chapter 10: “Application Notes” - Dynamic
Braking.
Dynamic Braking
–
BRAKING [ 81]
–
FALSE
TRUE
–
[ 80] ENABLE
–
100 Ohm
–
[ 77] BRAKE RESISTANCE
–
0.1 kW
–
[ 78] BRAKE POWER
–
25
–
[ 79] 1SEC OVER RATING
–
MMI Menu Map
1
SETUP
2
MOTOR CONTROL
3
DYNAMIC BRAKING
ENABLE
BRAKE RESISTANCE
BRAKE POWER
1SEC OVER RATING
BRAKING
Parameter Descriptions
ENABLE
Range: FALSE / TRUE
Enables operation of the dynamic braking block.
BRAKE RESISTANCE
Range:1 to 1000 Ohm
The value of the load resistance.
BRAKE POWER
Range: 0.1 to 510.0 kW
The power that the load resistance may continually dissipate.
1SEC OVER RATING
Range: 1 to 40
Multiplier that may be applied to BRAKE POWER for power overloads lasting no more than 1
second.
BRAKING
Range: FALSE / TRUE
A read-only parameter indicating the state of the brake switch.

Parker 690+ series Specifications

General

Frequency	50/60 Hz
Overload	150% for 60 seconds
Communication Options	Ethernet
Protection Rating	IP20
Operating Temperature	0°C to 55°C
Programmability	Yes
Communication Ports	RS485
I/O Capability	Digital and Analog I/O
Programming Languages	Function Block Diagram
Dimensions	Varies by module