Delta Electronics none manual „ Simple Calculation Method

( ) : motor frame size, unit is in millimeters.

Revision March 2008, Doc. Name: 2007PDD23000011

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Regenerative Resistors

BR400W040

BR1K0W020

100W

300W

200W

The users can select the adequate regenerative resistors according to the allowable frequency by referring to the table below:

Allowable frequency when the servo motor run without load (times/min)

ECMA Series400W (60mm)

04 8608 21517

m = load/motor inertia ratio

400W

(80mm)

04

3279

8765

Chapter 6 Control Modes of OperationASDA-AB Series

For example:

When external load torque is a +70% rated torque and rotation speed reaches 3000r/min, if using 400W servo drive (rated torque: 1.27Nt-m), then the users need to connect a external regenerative resistor which power is 2 x (0.7 x 1.27) x (3000 x 2 x π/ 60) = 560W, 40Ω.

„Simple Calculation Method

The users can select the adequate regenerative resistors according to the allowable frequency required by actual operation and the allowable frequency when the servo motor runs without load. The allowable frequency when the servo motor run without load is the maximum frequency that can be operated during continuous operation when servo motor accelerate from 0r/min to rated speed and decelerate from rated speed down to 0r/min. The allowable frequencies when the servo motor run without load are summarized in the following table.

Allowable frequency when the servo motor run without load (times/min)

	100W	200W	300W	400W	400W	500W	600W	750W
ECMA Series				(60mm)	(80mm)
	01	02	03	04	04	05	06	07
Allowable Frequency	-	-	-	1275	519	43	41	319
(times/min)
	900W	1.0kW	1.0kW	1.5kW	2.0kW	2.0kW	2.0kW
ECMA Series		(100mm)	(130mm)		(100mm)	(130mm)	(180mm)
	09	10	10	15	20	20	20
Allowable Frequency	31	137	42	31	82	24	10
(times/min)

( ) : motor frame size, unit is in millimeters.

When the servo motor runs with load, the allowable frequency will change according to the changes of the load inertia and rotation speed. Use the following equation to calculate the allowable frequency.

Allowable frequency =	Allowable frequency when serv o motor run without load		x	Rated s peed	2 times
		m + 1		Operating speed		mi n.

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