Braking resistor
In regenerative braking mode, the electric motor feeds braking energy into the intermediate circuit of the frequency inverter, causing the intermediate circuit voltage to rise. A braking resistor absorbs this energy and converts it into heat: part of it immediately, the rest after the braking process has been completed and the resistor has cooled down.
The characteristics of the load cycle (duty cycle / braking time and cycle time) are therefore important for the design of the braking resistor. In addition, the braking power PBr , i.e. how quickly the energy is dissipated, and the minimum resistance value Rmin , which is specified by the frequency inverter, are required.
The resistance value recommended by us is significantly higher than the minimum resistance value due to manufacturing tolerance and temperature coefficient. A safety margin of approx. 20% is calculated here (R = 1.2 x Rmin). This rules out possible damage to the inverter components due to excessive currents.
We will be happy to calculate the necessary braking resistor for the corresponding duty cycle ED based on the braking power, braking time and min. resistance value specified by you. Please send an e-mail to service@elektromotoren.de.
- Load resistance device in steel mesh construction
- Continuous powers up to 500 kW depending on configuration
- Parallel-connectable for larger powers
- Manufacture tolerance: +/-10 %
- Degree of protection: IP20
- Change in resistance between cold and hot operating states: Approximately +15 %
- For ground installation
- Galvanized steel sheet housing, closed all around
- Protective grids at the bottom and top
- External ventilation by built-in axial fans
- Fan supply: 3 x 400 VAC, 50 Hz
- Airflow monitoring by wind vane relays
- Air outlet at top
- Connection to terminals in the device
- Clamping accessible after disassembly of the front cover
The required clamps are mounted on a strip in the lower part of the device and are accessible after disassembly of a cover. Underneath this is an unbored cable lead-in strip which can be provided on the customer side with corresponding bores for cable glands for strain relief.
By using steel mesh elements with a type power of approximately 1.100 W to 1.700 W per steel mesh with external ventilation, a power range of up to 500 kW per device can be covered. The specified powers are achieved in the operating hot state. Greater powers can be achieved by connecting several devices in parallel.
Instructions for installation and operation:
The resistance shall be loaded only when the fan is running. After the load has been switched off, the fan must continue to run for at least 2 minutes to cool the resistors. When installed in buildings, adequate ventilation and ventilation of the installation space shall be ensured. Installation in air shafts is not permitted due to the risk of overheating.
Short-circuit resistant wire-wound flat resistor, manufacturing resistor
tolerance +/-10%, in the blue anodized aluminum housing, suitable
for use in harsh environments, including outside switchgear cabinets,
Connection to stranded wires, version with 2 PTFE stranded wires, AWG 14/19 (2,1 mm2), 0,5 m long. Voltage range up to 848 VDC.
- Very flat, compact design
- Short circuit fixed
- Self-extinguishing
- Protection level possible up to IP 67
- Useable in a harsh environment
- Greater continuous performance through direct assembly on heat sink/cooling surface
- Easy assembly by T-groove
By directly mounting on a suitable cooling surface or a cooling body, the continuous power can be increased or the surface temperature can be lowered. Typical factors for increasing the power are 1,5 to 5, depending on the type, ventilation and size of the cooling surface/heat sink.
Various mounting angles are available as accessories, which enable different mounting types.
Note:
Continuous overtemperature values of 200 K should not be exceeded, otherwise the protection level may be affected! The declared power values apply to continuous power. They can be increased in short-term operation as a function of the relative on-time (ED) by multiplication by the corresponding overload factors (ÜF) from the attached table.
Option: Temperature switch (..Q) (only for type GW..Q.). Not for GY.
For temperature monitoring, this type can be equipped with a 180° C temperature switch, which is prepared with 2 strands for connection.
Type designation then: GWADQ...
Application
as a braking resistor for frequency inverters, for example. Due to the high degree of protection, the resistors can also be mounted directly on the frequency inverter or motor in a rough environment outside of switchgear cabinets without any problems, if the strands are mechanically protected.
Cemented wire-wound tube fixed resistance, manufacturing tolerance +/-10%, in the galvanized sheet steel housing with side parts and
perforated cover, suitable for mounting on the switchgear cabinet, and for mounting on wall or mounting plates,
connection on the integrated overcurrent relay in the attached terminal box with PG9 and PG11 (up to 13 A) or with M12 and PG16-Kabelcable glanden
Type of connection: an therm. Excess relays
Degree of protection: IP20 When mounted on a suitable surface
Voltage range: up to 3 x 500 VAC and derived DC voltages
for use on drive controllers (brake transistors) in aluminium housings
anodised, Degree of protection IP65
Rated power 100 W (250W at ED = 35%, θA = 20°C)
Tolerance (resistance) ± 5 [%] (room temperature)
Maximum permissible operating voltage (taking into account "intrinsic safety") ≤ 700 AC [V] ≤ 1.000 DC [V]
Maximum permissible operating voltage (considering cCSOff and UL) ≤ 600 AC [V] ≤ 848 DC [V]
Energy consumption 4.000 [J] (for 1,2 s (1% ED))
Energy consumption 8.000 [J] (for 7,2 s (6% ED))
Inductance ≤ 30 (f = 300 kHz, Umess = 50 mV)
Dimensions BxHxL 80x15x110 mm
Cable length 510 ±40 mm Ø AWG16 or 1,5 mm2 PTFE insulated
*For four times the type power and free convection.
1. No short circuit, 2. No body closure, 3. Self-extinguishing, 4. No melting of the housing.
Type power always corresponds to 35% ED of the respective resistance type
Short-circuit-proof, "intrinsically safe"* braking resistor
for use on drive controllers (brake transistors) in aluminium housings
anodised, Degree of protection IP65
Rated power 200 W (500 W at ED = 35%, θA = 20°C)
Tolerance (resistance) ± 5 [%] (room temperature)
Maximum permissible operating voltage (taking into account "intrinsic safety") ≤ 700 AC [V] ≤ 1.000 DC [V]
Maximum permissible operating voltage (considering cCSOff and UL) ≤ 600 AC [V] ≤ 848 DC [V]
Energy consumption 7.500 [J] (for 1,2 s (1% ED))
Energy consumption 15.000 [J] (for 7,2 s (6% ED))
Inductance ≤ 30 (f = 300 kHz, Umess = 50 mV)
Dimensions BxHxL 80x15x216 mm
Cable length 510 ±40 mm Ø AWG16 or 1,5 mm2 PTFE insulated
*For four times the type power and free convection.
1. No short circuit, 2. No body closure, 3. Self-extinguishing, 4. No melting of the housing.
Type power always corresponds to 35% ED of the respective resistance type
for use on drive controllers (brake transistors) in aluminium housings
anodised, Degree of protection IP65
Rated power 400 (1000 at ED = 35%, θA = 20°C)
Tolerance (resistance) ± 5 [%] (room temperature)
Maximum permissible operating voltage (taking into account "intrinsic safety") ≤ 700 AC [V] ≤ 1.000 DC [V]
Maximum permissible operating voltage (considering cCSOff and UL) ≤ 600 AC [V] ≤ 848 DC [V]
Energy consumption 13.500 [J] (for 1,2 s (1% ED))
Energy consumption 26.000 [J] (for 7,2 s (6% ED))
Inductance ≤ 30 (f = 300 kHz, Umess = 50 mV)
Dimensions BxHxL 80x30x216 mm
Cable length 510 ±40 mm Ø AWG16 or 1,5 mm2 PTFE insulated
*For four times the type power and free convection.
1. No short circuit, 2. No body closure, 3. Self-extinguishing, 4. No melting of the housing.
Type power always corresponds to 35% ED of the respective resistance type