Power supplies offer steady and accurately controlled electrical energy to various equipment. Generally, lab instruments have built-in power supplies that allow them to be plugged into a common electrical outlet.
Initially, the power supply uses a rectifier in order to convert the AC or alternating current to DC or direct current. The latter is the most commonly used in devices and instruments. DC accumulates the power and adjusts the voltage or current upward or downward to meet the instrument’s needs.
Lab Power Supplies
Laboratories such as academic labs and research and development laboratories, use power supplies in order to run their basic equipment like electrochemistry of electroplating or to facilitate direct current in the same way as batteries. For instance, biology laboratories leverage power supplies to run gel electrophoresis devices.
Electrical laboratory power supplies are available in three types based on the kind of work being executed. Constant voltage supplies are the ones that offer configurable DC voltage. This is adjustable over a particular range, including zero voltage. These current supplies output regulates the current irrespective of the voltage. Such devices can either provide current or voltage.
The most commonly used avenues for lab power supplies are fabrication laboratories, design, and electrical testing. During the designing process, the prototype testing does not integrate power supply, so the design has to use one of the types of power supplies based on the product specifications.
Additionally, power supplies are also used to design as well as troubleshoot sub circuits and further repair any issues with circuits or instruments.
Varying current or voltage is commonly used when working on an electrical circuit prototype, which facilitates a specific task such as signal processing, timing, counting, etc. This is useful when you want to compare how a particular circuit runs at varying voltages.
Parameters to Consider When Investing in Lab Power Supplies
While the parameters vary depending on the lab device, here are some key considerations to look into when investing in laboratory power supplies.
This factor verifies how accurate the regulated parameter works against its theoretical value. Uncertainties in output primarily occur because of the error terms in a digital to analog converter (DAC). The accuracy setting is tested by measuring regulated variables with the derivative measurement system, which is connected to the output of a power supply.
It is referred to as the smallest variation in the current or voltage settings that can be selected. The feature limits the settable discrete levels.
Additionally, a DAC embedded with a larger number of bits develops finer resolution. However, when there are corrections for gain and offset errors, resolutions occur to be less than bits.
- Readback Accuracy
It signifies how precise the internally-measures values are to a particular theoretical value of the voltage output. This is measured once the setting accuracy is added.
- Readback Resolution
This is referred to as the smallest change within the internal-measured output current or voltage, which is detectable by the power supply. It is typically displayed in absolute value; however, it can also be expressed as a full-scale percentage.
- Power Stability
Over the course of years, the performance of the power supply is likely to change. Ensuring long-term performance stability requires verification as well as calibration on a regular basis.
- Temperature Stability
Accuracy of the power supply is measured above a temperature range, which is generally between 20-degree Celsius and 30-degree Celsius.
- Line Regulation
It is defined as the measure of the capability of the power supply to maintain the voltage or current output while there is variation in the AC line input voltage as well as frequency.
- Load Regulation
It is a measure of the potentials of the output current or output voltage to stay constant during the load variation.
- Ripple and Noise
Spurious AC components on the output of a DC supply are generally known as PARD or Periodic and Random Deviation. Moreover, ripple is defined as the periodic AC on the output. When displayed in a particular frequency domain, the ripple is displayed as spurious responses.
Contrary to ripple, the occurrence of noise is completely random. It encompasses a wide spectrum, and when viewed in a frequency domain, noise manifests as a rise in the baseline.
There you have it, everything that you need to know about lab power supplies. By referring to the information mentioned above, you can pick the right power supplies for your lab.