9 Specifications
9.1 Ambient Conditions
Environment
Ambient temperature range -40 to 70 °C
Temperature range during storage/transport -40 to 70 °C
Maximum temperature at housing 300 °C
Maximum relative humidity 5-85%, non-condensation during operation
Power derating as a function of ambient temperature. (100% power rating and pulse-load):
- Steel grid brake resistors, IP20 Continuous power 100% @ 40 °C to 70% @ 70 °C, linear
- Aluminum-housed compact brake resistors, IP21 Continuous power 100% @ 40 °C to 75% @ 70 °C, linear
- Aluminum-housed brake resistors - compact and flat-pack, IP54 Continuous power 100% @ 40 °C to 75% @ 70 °C, linear
- Aluminum compact brake resistors, IP65 Continuous power 100% @ 40 °C to 50% @ 70 °C, linear
Power derating at vertical mounted resistor (wall-mounted) when mounted horizontal (100% power rating and pulse-
load):
- Aluminum-housed flat-pack brake resistors, IP54 No derating
- Aluminum-housed compact brake resistors, IP21, IP54, IP65 -20%
Cooling requirements:
The brake resistors are cooled by free natural convection. The power ratings of the resistors refers to cooling conditions
with free natural cooling. The requirements for minimum clearances must be observed during installation.
Derating at high altitudes 100% @ 1000 m above sea level
Derating at high altitudes 94% @ 1500 m above sea level
Derating at high altitudes 82% @ 3000 m above sea level
9.2 General Electrical Specifications
Electrical specifications
Resistance tolerances ±10%
Insulation > 20 MΩ @ 1000 V
Dielectric strength 2500 V AC for 1 min.
Operating voltage:
- Aluminum-housed compact brake resistors, IP54 UL: 600 V AC/600 V DC
- Aluminum-housed compact brake resistors, IP54 IEC: 690 V AC/1100 V DC
- Aluminum-housed flat-pack brake resistors, IP54 UL: 1000 V AC/1400 V DC
- Aluminum-housed flat-pack brake resistors, IP54 IEC: 1000 V AC/1400 V DC
- Aluminum-housed compact brake resistors, IP21, IP65 UL: 600 V AC/600 V DC
- Aluminum-housed compact brake resistors, IP21, IP65 IEC: 690 V AC/1100 V DC
- Steel grid brake resistors, IP20 IEC: 690 V AC/1100 V DC
Power rating (continuous load 100%) with and without temperature switch
- Without temperature switch 100% of continuous power rating @ 40 °C
- With temperature switch, steel grid brake resistors, IP20 100% of continuous power rating @ 40 °C
- With temperature switch, aluminum-housed brake resistors,
IP21, IP54, IP65 Minimum 80% of continuous power rating @ 40 °C
- With temperature switch, aluminum-housed brake
resistors, IP21, IP54, IP65
Temperature switch enables at ≥80% of the continuous power
rating @ 40 °C
Electrical data temperature switch:
- Steel grid brake resistors, IP20 10 A, 250 V AC, normally closed (NC). Enables at 260 °C
- Aluminum-housed brake resistors, IP21, IP54, IP65 2 A, 250 V AC, normally closed (NC). Enables at 180 °C
Specifications Design Guide
66 Danfoss A/S © Rev. 05/2014 All rights reserved. MG90O202
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