Resistors
Resistor Products
Ohmic Control Resistors have been developed over a period of seventy years and are available in many different configurations of strip, plate and coil types covering a wide field of applications.
All resistor units can be supplied as open unprotected or installed in a housing for either indoor or outdoor use. Housing can be made from galvanized, powder coated steel or stainless steel materials. Whilst a range of standard units are available, designs to suit client specifications can be offered.
Resistor Banks
Two standard bank lengths 610 and 915mm have evolved over the years, although many different sizes are provided to match application and space limitations. Materials used for grid plates is a high resistivity, low temperature co-efficient, stainless steel stocked in 0.5, 0.8, 1.0, 1.2 and 1.6mm thickness, plates vary in width and length providing an extensive range of rating options.
Standard plates are cut from coil and further punched to introduce a series of convolutions, which increases plate resistance.
Plates are welded together to form a continuous current path with welded take off terminal points. Maximum number of plate per standard bank varies with material thickness, plates can be mixed with the bank.
| Thickness | Plate 610 mm | Plates 915 mm |
| 1.6 | 64 | 112 |
| 1.2 | 68 | 120 |
| 1 | 70 | 126 |
| 0.8 | 72 | 130 |
Other sizes can be made to suit application
| Standard plate types and rating | ||||
| Type | Ohms (Ω)/Plate | Cont Amp 250 °C | Cont Amp 500 °C | Amp 10 sec 500 °C |
| 1216 | 0.0466 | 37 | 61 | 280 |
| 1212 | 0.0620 | 32 | 53 | 220 |
| 1210 | 0.0725 | 29 | 48 | 190 |
| 1208 | 0.0931 | 27 | 44 | 140 |
| 816 | 0.0205 | 57 | 91 | 370 |
| 812 | 0.0272 | 49 | 79 | 250 |
| 810 | 0.0323 | 45 | 72 | 240 |
| 808 | 0.0410 | 39 | 64 | 180 |
| 616 | 0.0102 | 79 | 126 | 430 |
| 612 | 0.0141 | 69 | 109 | 350 |
| 610 | 0.0168 | 62 | 99 | 290 |
| 608 | 0.0215 | 55 | 92 | 210 |
| 416 | 0.0054 | 117 | 181 | 600 |
| 412 | 0.0073 | 102 | 157 | 450 |
| 410 | 0.0080 | 93 | 143 | 350 |
| 408 | 0.0107 | 86 | 130 | 280 |
| Low current plates (two rows per bank) | ||||
| Type | Ohms (Ω)/Plate | Cont Amp 250 °C | Cont Amp 500 °C | Amp 10 sec 500 °C |
| 1012 | 0.0595 | 27 | 41 | 165 |
| 1010 | 0.0688 | 25 | 38 | 135 |
| 1008 | 0.0873 | 21 | 32 | 85 |
| 1005 | 0.1620 | 14 | 21 | 60 |
| High current strip type | ||||
| Type | Ohms (Ω)/Plate | Cont Amp 250 °C | Cont Amp 500 °C | Amp 10 sec 500 °C |
| 0880 | 0.00485 | 130 | 185 | 680 |
| 1080 | 0.0039 | 145 | 210 | 770 |
| 1280 | 0.00232 | 160 | 230 | 970 |
| 10100 | 0.0031 | 185 | 265 | 970 |
| 12100 | 0.00256 | 200 | 285 | 1220 |
| 12120 | 0.0021 | 240 | 345 | 1350 |
| 16100 | 0.00187 | 230 | 330 | 1550 |
| 16120 | 0.00156 | 275 | 395 | 1829 |
| 16140 | 0.0013 | 320 | 460 | 2180 |
Neutral Earthing Units
Enclosed housing outdoor type IP23 to IP 55 often built to suit client specifications. Typical standard range, 10 sec rating to IEEE 32.
| 3.3 to 132kV, other sizes can be made to suit application. | ||
| 3.3kV | 100 A | 19.0 Ω |
| 3.3kV | 200 A | 9.5 Ω |
| 3.3kV | 400 A | 4.9 Ω |
| 6.6kV | 100 A | 38.0 Ω |
| 6.6kV | 200 A | 19.0 Ω |
| 6.6kV | 400 A | 9.5 Ω |
| 11kV | 100 A | 63.5 Ω |
| 11kV | 200 A | 31.8 Ω |
| 11kV | 400 A | 15.9 Ω |
| 11kV | 800 A | 7.9 Ω |
| 22kV | 100 A | 127.0 Ω |
| 22kV | 200 A | 63.5 Ω |
| 22kV | 400 A | 31.8 Ω |
| 22kV | 800 A | 15.9 Ω |
| 36kV | 100 A | 208 Ω |
| 36kV | 200 A | 104 Ω |
| 36kV | 400 A | 52 Ω |
| 36kV | 800 A | 26 Ω |
| 36kV | 200 A | 17.3 Ω |
66kV and 132 kV also other current ratings on request.
Isolating switch and current transformers can be incorporated. External or internal connection bushes or direct onto resistor banks. Housing can be supplied in galvabond, powder coated steel or stainless steel
Other Applications
- Dynamic Braking, Current and time to suit application
- Secondary resistance starters, designed to suit starting characteristics, rotor voltage, torque and current limitations
- Harmonic filter resistors, for use with capacitors and inductors
- High Current limitation resistors
- Load banks, fan or natural cooling
For more information about Ohmic Controls’ services or to speak to one of our friendly staff, call now on (02) 9820 5055.