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Many lab processes—from filtration to more advanced techniques—require a vacuum pump. Keeping that vacuum at a consistent, optimized level really makes some processes work better. Imparting traditional-style control upon a pump, though, creates a fluctuating level of vacuum. To solve that problem, VACUUBRAND, Inc. (Essex, CT) introduced its VARIO® technology for diaphragm vacuum pumps in 1997. Now, moving the technology ahead even more, the company recently released the PC3001 VARIO® select vacuum system. “The PC3001 VARIO® select is a great solution for quite a few different situations,” says Scott Leahy, Director of Technical Marketing at VACUUBRAND, Inc. “Some of the best kinds of applications for the VARIO® select pumps are evaporative applications like rotary evaporation or distillation.”
Conventional systems use a single-speed vacuum pump and a controller, which is a combination gauge and switch. “The switch interrupts the pump when the vacuum reaches a predetermined point—the setpoint—and reestablishes the pumping when the vacuum level creeps back up to a pressure slightly above—similar to the way a home thermostat works with a furnace or air conditioner,” explains Akbar Anwari, Marketing Manager at BrandTech® Scientific, Inc. (Essex, CT). “For a number of technical reasons, the pump typically remains running full speed and a valve is opened and closed between the pump and application, rather than switching it on and off.” He describes this as “a rather inefficient way to operate.”
The VARIO® technology uses a variable-speed pump. “In its simplest implementation, it can maintain a vacuum setpoint by matching the pumping speed to the application for tight ‘zero hysteresis’—or no variation—control,” Anwari explains. “More significantly, through innovative software by measuring pressure change in the application over time versus pumping speed, the ‘Automatic’ mode can find and follow boiling-point curves and continuously optimize the vacuum for the fastest process times in evaporative applications without uncontrolled boiling, known as ‘bumping,’ that can result in sample loss.” Less sophisticated techniques require users to know the vacuum setpoints before running a process.
The new PC3001 VARIO® select vacuum system offers even more features that make the instrument easier and more efficient to use.
PC3001 VARIO® select.Top-flight features
Even as just a benchtop device, the PC3001 VARIO® select vacuum system delivers many useful attributes. One of those is the interface.
“The application-based interface is a major step forward in the state-of-the-art,” Leahy says. “The interface is intuitive and familiar to anyone who has used a smartphone.” This system includes applications for common lab-vacuum processes—rotary evaporation, filtration, vacuum drying ovens, vacuum concentrators, etcetera—which a user can get going very quickly, just by choosing the process and hitting ‘start.’
It’s as easy to get data out of the system as it is to run it. “The VACUU·SELECT® controller also has two USB slots so that you can plug in a thumb drive and download process data, or transfer applications from one pump to another,” Leahy says. “And the controller can even alert you when it is time to change the diaphragms and valves in the pump.” Since these components can last for over 15,000 hours of operation, it’s easy to forget when they need service. “This helpful service reminder prevents that problem,” Leahy says.
If the system doesn’t provide the exact procedure that a user needs, custom processes can be easily created. A scientist can construct unique workflows “by dragging-and-dropping ‘building blocks’ to assemble complex procedures in minutes,” Anwari says.
This instrument also includes features of previous members of the VARIO® family, such as automatic adjustment of the vacuum level and pumping speed. Anwari points out that the family’s ongoing features also include “whisper-quiet operation, high performance, and service intervals measured in tens of thousands of hours.”
An array of applications
Given the ability to run common vacuum processes and program new ones, the PC3001 VARIO® select vacuum pump offers a wide range of uses.
As mentioned, this pump works well with rotary evaporation. In fact, Anwari calls this the pump’s “most popular application.” This application evaporates solvents as rapidly as possible by using heat, increased surface area, and vacuum. Moreover, the boiling points change as solvents evaporate, which makes this process unstable. “The continuous adaptation and adjustment of vacuum levels allow for fast process times without sample loss due to bumping,” Anwari says.
The pump also supports several different vacuum procedures. Since the VACUU·SELECT® controller comes loaded with applications for a wide range of common vacuum processes, “it’s very easy for a researcher to complete a series of processes using a single VARIO® select pump, with each of those processes being conducted with optimal conditions,” Leahy explains. “For example, a sample can first be placed in a rotary evaporator and have the majority of the solvents removed automatically using the ‘Automatic Evaporation’ application. Then, the sample can be placed in a vacuum oven or filtered, using those tailored applications, in order to complete final drying.”
Another top application of the PC3001 VARIO® select that Leahy mentions is repeating different variations of a process. “For example, it’s very easy to create different automatic evaporation processes that are configured for different solvent mixtures so that you can get repeatable experimental conditions and repeatable experimental results,” Leahy says. This is a great help in good lab practice (GLP) and good manufacturing practice (GMP) settings, he adds.
This collection of features and applications makes the PC3001 VARIO® select a valuable addition to any lab that needs to use a vacuum pump. As VACUUBRAND, Inc. points out, the PC3001 VARIO® select is the “easiest to operate vacuum system ever!” That ease of use, plus the platform’s many other features, make this a VARIO® worth looking at for labs of all sorts.
Mike May is a freelance writer and editor living in Texas. He can be reached at [email protected]