SK 54xE – Users Manual for Frequency Inverters
36 BU 0505 EN-3021
2.6 Brake resistor (BR)
CAUTION
Danger of burns
The heat sink and all other metal components can heat up to temperatures above 70 °C.
Touching such components may cause local burns to the affected parts of the body (hands, fingers, etc.).
To prevent such injuries, allow sufficient time for cooling down before starting work - the surface temperature
should be checked with suitable measuring equipment. In addition, keep a sufficient distance from adjacent
components during installation, or install protection against contact.
During dynamic braking (frequency reduction) of a three-phase motor, electrical energy is returned to
the inverter. An external brake resistor can be used in order to prevent the FI from being shut down
due to overvoltage. With this, the integrated brake chopper (electronic switch) pulses the intermediate
circuit voltage (switching wave approx. 420 V / 775 V (/825 V) DC, according to the mains voltage)
(115 V, 230 V/400 V(/500 V)) to the brake resistor. Here the excess energy is converted into heat.
For inverter powers up to 7.5 kW (230 V: bis 4,0 kW) a standard bottom-mounted resistor (SK BR4-
..., IP54) can be used. Approval: UL, cUL
Note: Brake resistors cannot be directly mounted below …-CP (ColdPlate) devices.
SK BR4-... Size 1
SK BR4
-... Size 2
Fig. 3: Bottom-mounted brake resistor SK BR4-...
For frequency inverters above 3kW chassis-mounted resistors (SK BR2-..., IP20) are also available.
These must be mounted in the control cabinet, close to the frequency inverter. Approval: UL, cUL
SK BR2-... Size 3 SK BR2-... Size 4 and above
Fig. 4: chassis brake resistor SK BR2-...
Pos: 46 /Anleitungen/ Elektronik/FU und St arter/2. Montage und Inst allation/Zubehör/ Bremswiderstand/SK 500EElektrisc he Daten Bremswiderstand [ SK 500E] @ 6\mod_14220171771 29_388.docx @ 200290 @ 3 @ 1
Das verknüpfte Bild kann nicht angezeigt werden. Möglicherweise wurde die Datei
To Next Page
Loading...
