High voltage and current measurement on rolling stock

Key facts about the application

Sector

Railway industry | Rolling stock

Application

Monitoring and controlling traction motors and monitoring the intermediate circuit voltage in traction converters or auxiliary power converters

Measurement parameters

Up to ±4500 V DC / ±3000 V AC, continuous isolation of up to 4800 V AC/DC, isolation test voltage of up to 20 kV AC

Main Requirements

SIL2/SIL3 safety

The high voltage transducer with the smallest footprint for rolling stock

The transducers in the P45000 series were developed to measure high direct and alternating current voltages at heavy-duty vehicles; rolling stock in particular. Some application examples are monitoring and controlling traction motors and monitoring the intermediate circuit voltage in traction converters or auxiliary power converters.

To a high degree, the voltage measurement input is isolated from the output and auxiliary power. The current output is compatible with commercial control inputs. The housing provides flexible mounting options: screwed on upright or flat, or snapped onto 35 mm DIN rails. The devices can even be stacked and mounted – even when space is very tight.

For the first time, applications that require functional safety can also be properly executed. The high-voltage transducer is certified for use in SIL2 systems and redundant for SIL3. With it, dangerously high voltages can be reliably detected.

Why Knick?
P45000 is the world’s first high voltage SIL transducer with SIL 2/3 certified functional safety. It can be stacked for a minimal footprint and offers flexible mounting options: DIN rails, flat or upright

Product highlights for measurements on rolling stock

P45000 – high voltage measurement

The P45000 high voltage transducer was developed for all direct and alternating current rolling stock, including diesel-electric vehicles for measurements up to 4500 V DC and 3000 V AC. Test voltage 20 kV AC and reinforced isolation up to 4800 V DC and 3700 V AC

P51000 – current measurement via shunt

The P51000 high voltage transducer enables overload-proof current measurement via shunt resistor from amperes to kiloamperes. Even strong electromagnetic fields cannot influence the measuring results. This leads to the highly precise acquisition of the current.

P52000 – voltage measurement

High-voltage transducers in compact design for voltage measurement up to 4800 V. The high-voltage contacts and connections are encapsulated. There is no danger of reciprocal effects with other components. With this design, no additional space between the terminal blocks is required: P52000 functions with 100 % safety

P52000VPD – voltage presence detector

The P52000VPD voltage presence detector is designed to detect voltages between 50 and 4200 V. The input signal is compared to a threshold value and the resulting binary information is galvanically isolated and transmitted to the output circuit. If the input voltage exceeds the threshold value, a solid state relay opens and signals that voltage is present at the input.

Matching Products

P45000 High Voltage Transducer / Transmitter | SIL 2/SIL 3 Functional Safety

Product number:

P45000

P51000 High Voltage Transducer / Transmitter | Calibrated and Switchable

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P51000

P52000 High Voltage Transducer / Transmitter | Calibrated and Switchable

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P52000

P52000 VPD High Voltage Transducer / Transmitter

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P52000VPD

P16800 Universal Speed Signal Doubler | Input speed sensor signal 10 … 33.6 V DC (max. 35 V) | Safe decoupling acc. SIL 4, safe transmission acc. SIL 2

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P16800

P16000 Pulse Frequency Conditioner | SIL 3 Non-interacting Extraction of RPM/Speed Sensor Signals

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P16000

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Voltage and current measurement in DC substations

Substations for direct power supply up to the upper one-digit MW range and the grid segments they supply must be effectively secured against short-circuits. The protective mechanism must reliably interrupt high currents as quickly as possible and limit the power flowing into the short circuit.

Speed signal doubling and conversion on rolling stock

P16800 makes it easy to retrofit rolling stock with control systems through the safe (SIL2/SIL4) conversion of speed sensor signals for odometry systems.

Railway

Electrical measurement in DC traction power substations and on rolling stock; conversion and duplication of speed sensor signals on-board rail vehicles.

Railway Industry Brochure

Overview of railway-specific applications and product solutions

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