A panel meter is a useful instrument that displays an input signal in either an analogue or a digital form. Some panel meters also feature alarm options and the ability to connect to a computer and transfer data. Panel meters use a sample of the current or voltage to create a visual representation of the measured value. Voltage measurements are read across the line, while current measurements are taken in series with the load, sometimes using shunts or transformers when the load current is greater than 10 amps. Analogue meters are able to display frequency, speed, current, voltage, temperature, strokes per minute or feet per second. Digital meters are very similar although they will usually also feature digital scaling of the display, relative to the input signal. Digital panel meters offer the greatest resolution although not necessarily the greatest accuracy and have an easier to read display, especially in low light. In cases where the input signal constantly changes, the analogue meter may be the preferable option. Digital panel meters can be reconfigured to display amps, volts, temperature or any other unit. Distrelec stocks analogue and digital panel meters from many manufacturers, such as Fujita, Christ-Elektronik and Ganz, as well as shunt resistors and convertors.