High Energy Slab Resistors
Ohmite's 500 Series Non-Inductive Bulk Ceramic Slab Resistors provide high power and energy dissipation in a compact size.
Non-inductive, high power slab resistors are available in a few different materials:
- Type 500BA slab resistor for high resistance applications
- Type 500SP slab resistors for high power applications
- Type 500AS slab resistors for high voltage, high energy and high resistance pulse applications
Specifications
Type 500SP High Power Slab Resistors
| Type | Length, inch (mm) | Resistance range, Ohms | Average power at 40°C (104°F) Amb., Watts | Peak energy at 40°C (104°F) Amb., Joules | Peak voltage, Volts | Resistor weight, Grams |
| 502SP | 2 (51) | 0.2-110 | 30 | 150 | 900 | 15 |
| 503SP | 3 (76) | 0.3-190 | 45 | 290 | 1900 | 22.5 |
| 504SP | 4 (102) | 0.4-280 | 60 | 480 | 2800 | 30 |
| 506SP | 6 (152) | 0.8-450 | 90 | 800 | 4700 | 45 |
| 508SP | 8 (203) | 1.0-630 | 120 | 1100 | 6700 | 60 |
| 510SP | 10 (254) | 1.3-800 | 150 | 1400 | 8500 | 75 |
Type 500AS High Voltage and High Energy Slab Resistors
| Type | Length, inch (mm) | Resistance range, Ohms | Average power at 40°C (104°F) Amb., Watts | Peak energy at 40°C (104°F) Amb., Joules | Peak voltage, Volts | Resistor weight, Grams |
| 502AS | 2 (51) | 5-1200 | 12 | 1500 | 8500 | 16 |
| 503AS | 3 (76) | 9-2200 | 18 | 2700 | 16000 | 24 |
| 504AS | 4 (102) | 13-3200 | 24 | 4000 | 23000 | 32 |
| 505AS | 5 (127) | 17-4200 | 30 | 5200 | 30000 | 40 |
| 506AS | 6 (152) | 21-5200 | 36 | 6400 | 36000 | 48 |
| 507AS | 7 (178) | 25-6200 | 42 | 7700 | 43000 | 56 |
| 508AS | 8 (203) | 29-7200 | 48 | 8900 | 50000 | 64 |
| 509AS | 9 (229) | 33-8200 | 54 | 10100 | 57000 | 72 |
| 510AS | 10 (254) | 37-9200 | 60 | 11400 | 65000 | 80 |
Type 500BA High Resistance Slab Resistors
| Type | Length, inch (mm) | Resistance range, Ohms | Average power at 40°C (104°F) Amb., Watts | Peak energy at 40°C (104°F) Amb., Joules | Peak voltage, Volts | Resistor weight, Grams |
| 502BA | 2 (51) | 1200-110000 | 10 | 700 | 3000 | 16 |
| 503BA | 3 (76) | 2200-210000 | 14 | 1200 | 5400 | 24 |
| 504BA | 4 (102) | 3200-300000 | 20 | 1800 | 8000 | 32 |
| 506BA | 6 (152) | 5200-490000 | 30 | 2900 | 13000 | 48 |
| 508BA | 8 (203) | 7200-680000 | 38 | 4100 | 18000 | 64 |
| 510BA | 10 (254) | 9200-870000 | 48 | 5200 | 22000 | 80 |
Standard Products
Material Types
Type SP
The type 500SP series slab resistor design enables the designer to minimize resistor package size and cost while providing unequalled high power performance and reliability. Material composition type SP is formulated to provide lower resistance values and higher derating temperatures. The higher derating temperatures translates to a higher wattage per inch than other material types. Typical applications for 500SP slab resistors are:
- Motor drive control resistors
- Power supply resistors
- Power generation/conditioning equipment resistors
- Power converter resistors
- Inverter resistors
- In-rush current limit resistors
- Soft start resistors
- Dynamic braking resistors
- RC snubber resistors
- RF dummy load resistors
- Capacitor charge/discharge resistors
Characteristics
| Product Characteristics | |
| Operating temperature | -55°C to +350°C (-67 to 662°F) |
| Temperature coefficient | + 0.2 to - 0.08 %/°C |
| Short time overload 1) | ±2% |
| Load life 2) | ±5% |
| Thermal shock 3) | ±3% |
| Moisture resistance 4) | ±5% |
Note: When required, type SP material can withstand short periods of use at red-heat conditions, i.e. up to 550-600°C (1031-1112°F)
- Max. % change after 5 cycles - 10 times rated power, 5 seconds on, 90 seconds off
- Max. % change after 1000 hrs. rated power 1-1/2 hours on; 1/2 hour off
- Max. % change after 10 cycles -55 to +125°C (-67 to 257°F)
- Max. % change when tested per MIL-STD-202, Method 103
Properties
| Physical Properties (Nominal) | |
| Density | 2.2-2.4 gm/cc |
| Specific heat | 0.24-0.26 cal/gm °C |
| Thermal conductivity | 0.14-0.16 cal/cm/°C/sec |
Power Rating Curves
Resistor Surface Temperature Rise Versus Power
Type AS
Material composition type AS is formulated to provide high voltage and high energy absorption in a singular package.
Applications:
- High voltage power supplies
- Capacitor charge/discharge
- Pulse test equipment
- Radar/broadcast transmitters
- Laser/imaging equipment
Type BA
Material composition type BA is formulated to withstand high energy and high voltage applications where the required resistance value is above the resistance values available in Type SP and Type AS resistors. Maximum continuous operating temperature is specified at 230°C.
Applications:
- DC Coupling and Filter Cap Discharge
- Voltage Balancing
- Pre-charge / Inrush Limit
- Voltage Divider
- Filter
- Snubber
- Crowbar
- Measuring
- EMI / EFI Test Circuits
- Test Loads
Type AS/BA Product Characteristics & Physical Properties
| Product Characteristics | |
| Operating temperature | -55°C to +230°C (-67 to 446°F) |
| Temperature coefficient | + 0.0 to -0.08 %/°C |
| Short time overload 1) | ±2% |
| Load life 2) | ±5% |
| Thermal shock 3) | ±3% |
| Moisture resistance 4) | ±5% |
Note: When required, type SP material can withstand short periods of use at red-heat conditions, i.e. up to 550-600°C (1031-1112°F)
- Max. % change after 5 cycles - 10 times rated power, 5 seconds on, 90 seconds off
- Max. % change after 1000 hrs. rated power 1-1/2 hours on; 1/2 hour off
- Max. % change after 10 cycles -55 to +125°C (-67 to 257°F)
- Max. % change when tested per MIL-STD-202, Method 103
| Physical Properties (Nominal) | |
| Density | 2.2-2.4 gm/cc |
| Specific heat | 0.22-0.24 cal/gm °C |
| Thermal conductivity | 0.003-0.006 cal/cm/°C/sec |
Power Rating Curves
Resistor Surface Temperature Rise Versus Power
