Baumuller BUG 2, Technical Description And Operations Manual

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Installation Accessories
34
BUG 3/2/20 Basic Feed Unit
5.96064.02
Baumüller Nürnberg GmbH
5.5.3 BUR Resistor Unit
Device Description
During the braking stage of converter-fed three-phase current drives, the system initially loads
the device-internal intermediate circuit capacitors with the fed-back electrical energy.
If there is still electrical energy available after loading, it can be additionally stored in an exter-
nal capacitor unit or converted to heat via device-internal or device-external resistors. Specifi-
cally for the latter purpose, a Type Series 6 device is provided that combines the resistors in a
force-ventilated way in a safe housing.
Electrical specifications
Resistor
1)
BUG20
BUG2
BUG3 R = 4
Ω
R = 8
Ω
R = 16
Ω
Rated Power P
V
≤
2 kW,
force ventilated, T
A
= 45 °C, mounted vertically
Peak Power P
V
≤
18 kW for t
≤
15 s
P
V
≤
36 kW for t
≤
7 s
Max. permissible ballast energy 270 kWs
Operating environm. temperature T
B
0 ... 45 °C
Coolant temperature range T
K
0 ... 45 °C
Storage temperature range -30 ... +70 °C
1)
When UL508C is considered: The resistor-units are only to
be used in connection with Baumüller-appliances of BUG and BUM61, 62 and 62T types.
Calculation
Kinetic energy
W J
n
m
=

 
 1
2
2
60
2
* *
*
π
Stored energy ( )
W C U U
m
= −
1
2
2
2
1
2
* *
Ballast energy W
V
= P
V
* t
The following are stored in the ca-
pacitor
with BUG 3 and BUG 21
with BUG 20 and BUG 2
BUK capacitor unit
W
el
= 3.8 Ws/unit
W
el
= 17.25 Ws/unit
W
el
= 345 Ws/unit
The following are burnt out in the
ballast resistor
Ballast
BUG 3
BUG 2
BUG 20
Ext. ballast BUR
W
el
= 13.5 kWs P
eff
= 200 W
W
el
= 24 kWs P
eff
= 400 W
W
el
= 55 kWs P
eff
= 900 W
W
el
= 270 kWs P
eff
= 2 kW
In cyclic operation, the power P of the ballast resistors is not to be exceeded.
ges
t
t P t P
P
...
2 2 1 1
+ ⋅ + ⋅
=