Bose MR-J2S- B Dynamic brake characteristics, 5 Dynamic brake operation diagram, Characteristics

11. CHARACTERISTICS

11.3 Dynamic brake characteristics

Fig. 11.5 shows the pattern in which the servo motor comes to a stop when the dynamic brake is operated. Use Equation 11.2 to calculate an approximate coasting distance to a stop. The dynamic brake time constant varies with the servo motor and machine operation speeds. (Refer to Fig. 11.6)

Forced stop(EM1) ONOFF

Lmax

Lmax

Vo

JM

JL

te

						V0		Time constant
				Machine speed
							te		Time
					Fig. 11.5 Dynamic brake operation diagram
V0	te		JL
60		1 JM			.......................................................................................................................					(11.2)
: Maximum coasting distance											[mm][in]
: Machine rapid feedrate										[mm/min][in/min]
: Servo motor inertial moment										[kg cm2][oz in2]
: Load inertia moment converted into equivalent value on servo motor shaft										[kg cm2][oz in2]
: Brake time constant (Fig. 11.6)											[s]
: Delay time of control section (Fig. 11.5)											[s]
(There is internal relay delay time of about 30ms.)

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