Ambient conditions
How much air a compressor actually delivers depends on the intake air. The IAC 500 sensor measures absolute pressure, temperature and humidity in the compressor room, so efficiency measurements are comparable and accurate.
Why measure ambient conditions
A compressor's free air delivery depends on the temperature, pressure and humidity of the intake air. Large temperature swings, for example between day and night, cause uneven delivery. That is why location and climate conditions are considered already when planning a compressor station.
When measuring compressor efficiency (specific power in kWh/m³), the flow is converted to ISO 1217 reference conditions (20 °C, 1000 mbar) or to the actual room conditions. This requires accurate intake air data.
CS Instruments models
Together with a data logger, flow meter and power meter, the IAC 500 forms a complete system for measuring compressor efficiency.
3-in-1 ambient sensor
Absolute pressure, temperature and humidity in the compressor room – for accurate compressor performance assessment.
Compressor efficiency
Mobile kit for measuring compressor efficiency and specific power.
4/8/12-input data logger
Intelligent data logger for all sensors: display, alarms, recording and energy analysis.
Pressure + temperature
2-in-1 pressure and temperature sensor with digital temperature compensation.
Comparison
| Model | Version | Temperature | Relative humidity | Absolute pressure | Outputs |
|---|---|---|---|---|---|
| IAC 500 | Stationary | -20…+60 °C, ± 1 K | 5…95 % RH, ± 3 % | 300…1100 hPa, ± 4 hPa | Modbus-RTU, PoE |
| DS 500 PM mobile | Portable | – | – | – | – |
| DS 500 | Stationary | – | – | – | Ethernet, Modbus RTU/TCP, 4 relays |
| PTS 500 | Stationary | -20…+125 °C | – | – | Modbus-RTU, PoE |
Efficiency measurement
The system from the CS Instruments catalogue for measuring compressor specific power.
Mobile data logger with up to 12 inputs collects and evaluates all measurements.
Reference flow meter to ISO 1217 or DIN 1343 in Nm³/h, Nm³/min or l/s.
Humidity, absolute pressure and temperature of the compressor intake air.
Total electrical power of the compressor – together with flow it gives kWh/m³.
How to choose
The IAC 500 records temperature, humidity and pressure at the compressor intake for a few days.
Day/night and summer/winter variations show whether ventilation is sufficient.
Cooler intake air from an outside intake or better ventilation saves energy.
Dirty intake filters can reduce capacity by up to 10 % – continuous monitoring reveals them in time.
FAQ
Cooler air is denser, so the compressor compresses more air mass per revolution. According to the CS Instruments catalogue, an intake temperature about 10 °C lower saves around 3 % of energy.
ISO 1217 defines reference conditions for compressor delivery (20 °C, 1000 mbar). To compare the measured delivery with the manufacturer's data, it is converted to these conditions – which requires the pressure, temperature and humidity of the intake air.
Yes. The IAC 500 has a Modbus-RTU output through which the DS 500 reads absolute pressure, temperature, relative and absolute humidity and dew point.
Related measurements
Fill in a short form and we will prepare a proposal for measurement equipment and implementation based on the medium, measuring range, and measurement objective.
