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Instruments

Standard capacitors

Highly stable standards

We have developed highly stable four terminal-pair capacitance standards of compact design. Their stability derives from using a ceramic dielectric and by keeping the standards at constant temperature using a two-stage oven.

Two BNC connectors are attached to the built-in platinum resistance thermometer (PRT) to monitor the internal temperature of the capacitor. Accurate capacitance measurement can be made via four terminal-pair coaxial BPO (MUSA) connectors. Each capacitor is housed in a metal box and requires only a simple 12 Volt DC supply to operate the temperature controller. A feature of this capacitor is that the value does increase by about 90 parts per million (ppm) with each factor of ten increase in the measurement frequency.

Features

  • Selected capacitance values in the range 50 pF to 1 μF are available
  • High stability
  • Capacitance value close to nominal
  • Small dissipation factor
  • Frequency dependence is ~90 ppm for each factor of 10 increase in measurement frequency
  • Compact design with standard four terminal-pair BPO (MUSA) connectors
  • Built-in two-stage oven controller with an independent 100 Ω PRT sensor as standard
  • 1 year warranty
  • Calibration certificate available

Specifications

Capacitance

Selected values between 50 pF to 1 μF available
  Within a tolerance of ± 100 to ± 500 ppm depending on value, at 1 kHz
Dissipation factor Around 0·00005 to 0·0005 depending on value at 1 kHz
Frequency dependence ~ 90ppm for each factor of 10 increase in measurement frequency
Drift ± 0·05 ppm/day typically
Stability (Short term) ± 0·01 ppm/hour
Max Working voltage 30 V rms
Warm-up time 1 hour  (allow 48 hours to stabilise before use)
Operating ambient temperature 15 °C to 24 °C
Relative humidity 20% to 60% non-condensing
Storage temperature range 5 °C to 70 °C
Power requirements 12 V DC ± 0·5 V
Power consumption 15 watts max. during initial warm-up, 2 watts after 1 hour, dependent on ambient temperature
Packaging 93mm high, 123mm wide, 125mm depth, plus 50 mm height of BPOs
Weight 1.4 kg
Warranty 1 year return to base

The best measurement capability, expressed as an expanded uncertainty (k = 2) is 70 ppm of nominal value, which applies to a wide range of instruments and test conditions.

Don’t see what you are looking for? Our diverse skill set enables us to provide bespoke solutions. Please contact us to discuss your requirements.

Contact us

Contact us

Our research and measurement solutions support innovation and product development. We work with companies to deliver business advantage and commercial success.
Contact our Customer Services team on +44 20 8943 7070