Full Remote Control for Bench and System Applications: Analog, RS-232, USB, LAN (LXI) or GPIB interfaces
Higher Voltages Without Lower Performance
The PLH series is a development of the best-selling New PL series of laboratory bench power supplies which is available in 15V, 30V and 60V variants (covered in a separate brochure and on our web site).
The PLH series retains the ultra compact format, high power density, and smart analog controls of the PL series but offers voltages up to 250V to cover applications beyond the capabilities of standard bench PSUs and into areas such as magnetics.
TTi has been at the forefront of laboratory power supply design for around thirty years during which it has re-defined the state-of-the-art for switch mode products with its innovative Mixed-mode and PowerFlex regulator designs. Demand for linear regulated PSUs has remained strong and continuing development of linear models has generated the lower cost ELR series, and the advanced QL series in addition to the ever popular PL series. The PLH and PLH-P series of linear regulated higher voltage dc power supplies joins a large family of PSUs with power levels from 15 watts up to 1200 watts.
Analog Controls with Digital Stability
As technology has changed, many products have moved from analog controls to digital ones. Although digital controls suit many instruments, they do not necessarily suit a bench power supply. Customer research shows that many users prefer the speed and simplicity of conventional analog controls for setting voltage and current. Digital controls may offer greater precision, but often at the expense of ease-of-use. With this in mind, the New PL series has retained the true analog controls of its predecessor.
The main disadvantage of analog controls is stability and security. The settings of analog potentiometers can drift over time. More importantly, the settings can be changed accidentally with potentially serious consequences.
The New PL series introduces S-Lock. One press of the Lock button transfers control of voltage and current from the analog controls to internal digital circuitry. This offers not just complete security, but exceptional stability as well with each setting controlled by an instrumentation quality DAC.
Linear Regulation for Ultra-Low Noise
Linear regulation still offers the lowest output noise and the best transient response (recovery time from a sudden current step).
Despite the high output voltages, the PLH series maintains output noise figures of below 2mV, and transient recovery times of better than 250μs. In addition, the lack of a high frequency switching circuit reduces radiated noise and common mode signals enabling the PLH series to be used in sensitive environments.
Choose a Voltage Range that Suits Your Task
When working with any particular piece of equipment, engineers often require a voltage source variable over only a narrow range. Set the voltage too high and damage might occur, set it too low and the circuit may reset. That’s where the V-Span function of the New PLH series comes in. It allows the user to redefine the end-stop values of the voltage control to define a specific voltage range.
For example:
An engineer is working on a circuit that will eventually operate from a peak rectified 110V rms ±5% supply. They use V-Span to set a Vmax of 164 volts (to prevent over-voltage damage) and a Vmin of 147 volts (to ensure that the circuit doesn’t reset). They now have a power supply which provides high resolution analog control over the exact voltage range they need. Vmin and Vmax can be set anywhere between zero and maximum output voltage subject only to Vmax > (Vmin + 0.1V). The fine control gives additional adjustment of ±1%.
Once set, the voltage span function can be turned on or off at the press of a button*.
Ultra Compact Using Minimum Bench or Rack Space
Ultra-Compact Design with Higher Power Efficiency and Near-Silent Cooling
The PLH series achieves an exceptional power density for a linear regulated power supply by offering up to 94 watts from a ¼ rack 3U sized casing. This gives it an unusually small bench footprint taking up less space on a crowded bench. For rack-mount application, up to four units can be mounted into a single slot.
Despite its small size and linear regulation, the PLH series generates relatively little heat through the use of an advanced phase controlled pre-regulator. This gives it significantly higher energy efficiency than conventional linear regulated designs, particularly when supplying voltages below maximum. The internal heat-sinks use fan-assisted convection cooling in order to remove the heat with minimal fan noise.