Nord Drivesystems SK 510P, Руководство с инструкциями по установке

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NORDAC PRO (SK 500P) – Manual with installation instructions
32 BU 0600 en-3221
2.3 Braking resistor (BR)
CAUTION
Hot surfaces
The braking resistor and all other metal components can heat up to temperatures above 70 °C.
• Danger of injury due to local burns on contact.
• Heat damage to adjacent objects.
Allow sufficient cooling time before starting work on the product. Check surface temperature with
suitable measuring equipment. Maintain an adequate distance to adjacent components or provide
protection against contact.
Information
To protect the braking resistor against overload, the electrical data of the braking resistor which is
used must be set in parameters
P555 , P556 and P557 .
During dynamic braking (frequency reduction) of a three-phase motor, electrical energy is returned to
the inverter. An external braking resistor can be used to prevent the FI from being shut down due to
overvoltage. With this, the integrated brake chopper (electronic switch) pulses the link circuit voltage
(switching threshold approx. 420 V / 775 V DC, depending on the mains voltage (230 V / 400 V)) to
the braking resistor. Here the excess energy is converted into heat.
For inverter powers up to 5.5 kW (230 V: up to 2,2 kW) a standard bottom-mounted resistor
(SK BRU5-..., IP40) can be used. Approval: UL - recognised
SK BRU5-…
Figure 2: Frequency inverter with bottom-mounted braking resistor SK BRU5-...
For frequency inverters above 3 kW 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