Toshiba VF-AS1 instruction manual Dynamic regenerative braking For abrupt motor stop, Function

E6581301

￿				*1￿
Input voltage"
Synchronized			ON
acceleration/dece
leration signal		"
(S1 terminal)	"	Inverter 1"
Motor speed"
			￿￿￿￿￿	￿￿￿￿￿
				Time"
		Inverter 2"	￿￿￿￿￿	￿￿￿￿￿

*1:Even with ￿￿￿=￿,￿,￿ functions are used, a motor may coast according to load conditions. In this case, try to adjust the parameter "￿￿￿￿" and "￿￿￿￿".

5.19Dynamic (regenerative) braking - For abrupt motor stop

￿ ￿￿￿

: Dynamic braking selection

￿￿￿￿￿: Dynamic braking resistance

￿￿￿￿￿￿: Dynamic braking resistor continuous capacity

￿￿￿￿￿￿: Braking resistance overload time

5 • Function

Dynamic braking is used in the following cases:

1)Need to stop the motor quickly.

2)The inverter trips because of an overvoltage (OP) during deceleration.

3)Fluctuation of load condition causes a regenerative power even at a constant speed such as press machine.

[Parameter setting]

Title			Function			Adjustment range			Default setting
￿￿￿		Dynamic braking selection				￿:Disabled			￿
						￿~￿:Enabled￿
￿￿￿		Dynamic braking resistance				￿￿￿~￿￿￿￿ ￿			According to model
									￿ Refer to page K-48.
￿￿￿￿		Dynamic braking resist#r				￿￿￿~￿￿￿￿￿ kW			According to model
		continuous capacity							￿ Refer to page K-48.
￿￿￿￿￿		Braking resistance overload				￿￿~￿￿￿￿￿ sec.			￿￿￿
		time
* Protection levels defined by ￿￿￿￿ (Refer to Section 6.14.2).
Note 1: The dynamic braking selection works on the following conditions.
					Inverter trip condition			Dynamic braking resistor
	Setting		Braking function	(The state of ￿￿￿ trip			ST-off condition
									overload detect
					is excluded)
		￿￿	Disabled		-		-	-
		￿￿				Enabled	Enabled		Protect
		￿￿				Enabled	Enabled		No Protection
		￿￿				Enabled	Disabled		Protect
		￿￿	Enabled			Enabled	Disabled		No Protection
		￿￿				Disabled	Enabled		Protect
		￿￿				Disabled	Enabled		No Protection
		￿￿				Disabled	Disabled		Protect
		￿￿				Disabled	Disabled		No Protection

Note 2: The time set using ￿￿￿￿ is the time for which the resistor sustains an overload. (Enter the time elapsed before the inverter trips if a load 10 times as large as the dynamic braking resistor continuous capacity specified using ￿￿￿￿ is applied.) There is no need to change resistance settings recommended by Toshiba (except DGP resistance setting).

Note 3: If the parameter ￿￿ is set to ￿~￿ (regenerative braking selected), the inverter will be set automatically so as to deal with the regenerative energy from the motor by means of a resistor, without taking any action to limit overcurrent. (The same function as ￿￿￿￿=￿)￿

Note 4: For inverters with ratings of 400V-200kW or more, set ￿￿ to ￿~￿ , because separate dynamic braking units are not included as standard equipment.

E-36