Different systems of lab spectrophotometers offer various features that are either standard or accessories to the equipment. One feature that is fairly standard is a Peltier or zipper package that allows flowthru and constant and continuous temperature control. This is going to be important when testing different materials that may be temperature sensitive. A sample compartment that can be adjusted to suit the size of the sample is another important accessory that is standard in most models of lab spectrophotometers. This provides more opportunity for testing even small sample sizes as opposed to having a standard sized sample for each and every test. Cuvette holds that have different positions are also an important feature that makes the equipment both practical and easy to use. Standard four position cuvette holders are ideal for almost every use and typically are all that a lab will require. Auto zero functions on your laboratory spectrophotometer are also standard on many models but are an important consideration. This function prevents unnecessary errors as technicians can always be assured that the equipment is zeroed and ready to use after each and every test.

Accuracy, dependability and the ability to repeat tests with the same results are the most important functions of a lab spectrophotometer. Since this equipment is likely to be used frequently in most labs it is essential that the data and information be accurate with each and every test run. This means that wavelength accuracy and wavelength repeatability have to be very specific, a good number is plus or minus two nanometers for most types of lab work.

The stray light within the laboratory spectrophotometer should be rated at less that zero point three percent to ensure that readings are consistent and repeatable regardless of the day or time when the reading and test was originally completed. Since most lab spectrophotometers will use a standard tungsten halogen lamp this is also an important consideration. This light source is highly dependable and consistent, again leading to repeatable readings without any concerns of deviations on tests.

A built-in printer with a lab spectrophotometer is a great feature and one well worth considering. Not only does it help with actually recording the results of the spectrophotometer, but it also can help your tests stay accurate and clear. The laboratory spectrophotometer's printer will generate a document that can then be recorded without any concern that numbers have been jotted down incorrectly or locating specific results on forms that may end up at the other end of the lab by the end of the day. In addition, the printer feature provides a back up of information for verification and retrieval if data is misplaced or lost. A built in printer can help the lab stay efficient, which is always the most important consideration.

Centrifugal machines can range from very basic to those with a lot of additional time and energy saving features. One really important consideration is the design of the mouth of the centrifuge that will allow for easy cleaning of those spills that are bound to happen. Metal or durable plastic construction also allows easy external cleaning and disinfecting. Variable speed controls, preset functions and timers, metal rotors and bowls, and options for handling different sizes of tubes are additional centrifuge features to consider. Since each lab will have different requirements, knowing that you are going to use the centrifugal machine for and buying one with the desired options is always the best option.

Different models of centrifugal machines offer different options for use. Some of the combination styles of machines have the added feature of being able to spin test tubes, capillary tubes or even the very tiny microtubes. This is done by a series of internal rotors that can be easily popped in and out by the technician. This versatility means that one centrifuge can provide service for a wide range of testing options.

Tachometers that are built into many of the new styles of centrifugal machines allow technicians to select the rotation speed and also go to a very fast spin to an almost immediate stop. Readings are also quickly available, meaning these centrifuge machines save both time and the need to re-spin and repeat tests. Safety shut offs are essential for lab safety and the don't unlock until the lid is securely in place and locked to the top of the unit. Many have a clear lid or viewing compartment for easy visibility into the centrifuge at all times during the operation. Settings can range from anything over zero rmps to up to twelve thousand on the highest settings in some models.

The new models and designs of centrifugal machines are built to be very quiet when in use. Like all lab equipment that is constantly operated it is essential to look for quiet options to keep the work environment as comfortable and noise free as possible. Cooling fans on the motors and vibration free operation have ended the days of the noisy centrifuge, even with the larger sized equipment. New bases that include suction type feet and non-skid base materials have also ended the movement of the machine. In the past, models would often shimmy across a work surface as the centrifuge spun, creating more problems and limiting the area the equipment could be used. Now, with the more modern style, the centrifugal machine is safe to use anywhere without the need for permanent attachment to the workspace surface.