Detuned capacitor banks
All electrical devices require active power to operate. Many electrical devices, such as electric motors, also require reactive power to operate. Reactive power can be drawn from the grid, but in that case, the network operator charges a reactive power fee. Another option is to produce reactive power locally using a detuned capacitor bank.
Reactive power requirement
Harmonic currents occur in electrical power systems due to nonlinear loads such as computers, frequency converters, and UPS systems. Harmonic currents cause, for example, increased losses and malfunctions in electrical equipment. The detuned capacitor bank filters out ordinary harmonic currents.
When selecting a detuned capacitor bank, it is essential to know the site’s reactive power requirement and how the requirement varies. The electricity bill usually reveals the reactive power requirement. In more complex installations, the reactive power requirement and harmonic currents can be determined through measurements.
Selecting a detuned capacitor bank
A detuned capacitor bank consists of appropriate compensation stages. The stages are selected based on variations in the site’s compensation requirements. Typically, a suitable combination of small (e.g., 12.5 kvar), medium (e.g., 25 kvar), and large (e.g., 50 kvar) compensation stages is required. The compensation stages are controlled by a regulator that switches them on or off according to the reactive power needed at any given moment. If a conventional floor-standing detuned capacitor bank is too large to fit or if floor installation is not an option, we recommend using a wall-mounted bank.
The detuned capacitor bank is tuned to a frequency that is not found in the network (in Finland, this is typically 189 Hz). Other tuning frequencies can also be used.
Features
– 400 V, 50 Hz
– Tuning frequency: 189 Hz
– Control with 6, 12, 18 or 24 steps, as required
– Cabling direction from above
– Filter fan
– Enclosure rating IP30
– Indoor installation, 0–35°C
Selecting a detuned capacitor bank
– Voltage level other than 400 V, such as 690 V
– Tuning frequency other than 189 Hz –
for example, 134 or 141 Hz.
– Outdoor installation: IP43, -25°C – (+35°C)
– Cable routing from the bottom or the side
– Slave battery without a controller
Reactive power calculator for dimensioning detuned capacitor banks
Enter the active power (kW), the power factor at the outset, and the desired power factor here. The calculator provides you with the required compensation power.
Power factor compensation
| Product | Power (kvar) | Stages (kvar) | Current (A) | Dimensions (width x depth x height) | Weight (kg) | Heat losses (W/kvar) | Fuse (A) | Cable (Cu/mm², recommended) | E number |
| TKF-E23/3+7.5+12.5/400-50-189 | 23 | 3 +7.5 + 12.5 | 33 | 800 x 600 x 1150 | 100 | 10.5 | 3 x 50 | 3 x 16 + 16 | 5714735 |
| TKF-E35.5/3+7.5+2x12.5/400-50-189 | 35.5 | 3 + 7.5 + 2 x 12.5 | 51 | 800 x 600 x 1150 | 115 | 10 | 3 x 80 | 3 x 25 + 16 | 5714737 |
| TKF-E45/7.5+12.5+25/400-50-189 | 45 | 7.5+12.5+25 | 65 | 800x600x1150 | 130 | 8.1 | 3x100 | 3 x 50 + 25 | 5714700 |
| TKF-E70/7.5+12.5+2x25/400-50-189 | 70 | 7.5 + 12.5 + 2 x 25 | 101 | 800x600x1150 | 150 | 7.7 | 3x160 | 3 x 70 + 35 | 5714704 |
| TKF-E75/2x12.5+2x25/400-50-189 | 75 | 2x12.5+2x25 | 108 | 800x600x1150 | 150 | 7.7 | 3x160 | 3 x 70 + 35 | 5714703 |
| TKF-E95/7.5+12.5+25+50/400-50-189 | 95 | 7.5+12.5+25+50 | 137 | 800x600x1150 | 180 | 7.3 | 3x200 | 3 x 120 + 70 | 5714707 |
| TKF-E100/2x12.5+25+50/400-50-189 | 100 | 2 x 12.5 + 25 + 50 | 144 | 800x600x1150 | 180 | 7.3 | 3x200 | 3 x 120 + 70 | 5714706 |
| TKF-E125/2x12.5+2x25+50/400-50-189 | 125 | 2x12.5+2x25+50 | 180 | 800x600x1150 | 190 | 7.3 | 3x250 | 2 x (3 x 70 + 35) | 5714766 |
| TKF-E150/2x12.5+25+2x50/400-50-189 | 150 | 2x12.5+25+2x50 | 217 | 800x600x1150 | 200 | 7.1 | 3x315 | 2 x (3 x 70 + 35) | 5714710 |
| TKF-E175/25+3x50/400-50-189 | 175 | 25+3x50 | 252 | 800x600x2000 | 280 | 6.7 | 3x315 | 2 x (3 x 95 + 50) | 5714712 |
| TKF-E200/2x12.5+25+3x50/400-50-189 | 200 | 2x12.5+25+3x50 | 288 | 800x600x2000 | 320 | 7 | 3x400 | 2 x (3 x 95 + 50) | 5714715 |
| TKF-E225/25+4x50/400-50-189 | 225 | 25+4x50 | 324 | 800x600x2000 | 350 | 6.7 | 3x400 | 2 x (3 x 120 + 70) | 5714716 |
| TKF-E250/2x25+4x50/400-50-189 | 250 | 2x25+4x50 | 361 | 800x600x2000 | 380 | 6.7 | 3 x 500 | 2 x (3 x 150 + 70) | 5714722 |
| TKF-E300/2x25+5x50/400-50-189 | 300 | 2x25+5x50 | 433 | 800x600x2000 | 450 | 6.7 | 3 x 630 | 2 x (3 x 185 + 95) | 5714724 |
| TKF-E300/6x50/400-50-189 | 300 | 6x50 | 433 | 800x600x2000 | 450 | 6.6 | 3 x 630 | 2 x (3 x 185 + 95) | 5714720 |
| TKF-E400/2x50+4x75/400-50-189 | 400 | 2x25+50+4x75 | 577 | 1200x600x1800 | 520 | 6.2 | 3 x 800 | 2 x (3 x 240 + 120) | 5714767 |
See our specialised banks
We also manufacture products with other features, such as products for different voltage levels or with non-standard dimensions.
Download the operating manual for the detuned capacitor bank
We conduct power quality measurements on-site and provide recommendations for corrective actions. We manufacture compensation and harmonic filtering products tailored to our clients’ needs at our own production facility. We provide equipment inspections and maintenance.
Download the reactive power guide
The guide provides a step-by-step overview of how to select a
detuned capacitor bank for reactive power compensation. After reading this, you will have a basic understanding of the topic, and you will be able to select the right equipment for your application. The table on the last page provides all the relevant technical information, including information for device installation.
Spare parts for detuned capacitor banks
***TKF spare parts are compatible with most detuned capacitor banks. For example, spare parts for older detuned capacitor banks from Nokia Capacitors, Alstom Grid, or GE Grid Solutions.
| Spare part | TKF spare part | TKF E-number | Nokian Capacitors component*** | Nokian Capacitors E-number*** |
| Capacitor unit | TKF-U12.5/400-50 | 5714728 | FL1D 15/400-50 15 kVAR | 5705322 |
| Capacitor unit | TKF-U25/400-50 | 5714729 | FL2D 50/400-50 50 kVAR | 5705326 |
| Capacitor unit | TKF-U50/400-50 | 5714730 | FL2D 50/400-50 50 kVAR | 5705328 |
| Reactive power controller | TKF-CXplus12 | 5714733 | NC-12 | 5705493 |
| Filter fabric | NC D filter | FILTER MAT AM25P | 5705794 | |
| Other | Whether you need a contactor, a detuned capacitor, a filter fan, or a thermostat, you can contact us! |
TKF's solutions are used at thousands of sites, ranging from office buildings to industrial facilities
Needs range from standard reactive power compensation to demanding applications that are critical to society. Hospitals (such as Tampere University Hospital and Satakunta Central Hospital in Finland), the Finnish Defence Forces, infrastructure projects (Helsinki Airport and the Helsinki metro), industry, real estate companies (VVO, Senate Properties), and electrical installations.
