STOLAB logo       Stow Laboratories Inc.

designs and manufactures  highly accurate industrial temperature measuring systems,
instruments,  gages,  and indicators,  electronic and digital thermometers,  calibrators,
sensors and accessories,  known as the  STOLAB PL SYSTEM (TM).

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You may have also found us as   Stow Lab,  Stow Labs,  Stolabs,  or  Stow Laboratories


Founded in 1966, STOLAB designs and manufactures industrial instruments, primarily the highly accurate PL SYSTEM for temperature measurement and control. Our products have earned a reputation for reliability, ease of use, and dependable performance. We are a small company, our phones are answered by people, not machines. If you need to measure temperature accurately, would like some application help, further product information, pricing, and ordering information, please contact us :

Mail, phone, fax or e-mail :

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A unique, patented design by Stow Laboratories Inc.

The STOLAB PL SYSTEM was designed for accurate, trouble-free, versatile, and reliable temperature measurement in industrial environments. It is also widely used in laboratories, hospitals, metrology, power generation, pipelines, and many other fields. Because it was designed and is manufactured as a complete system, it eliminates many common temperature measurement errors. PL SYSTEM users can add, replace, and interchange all system elements : sensors, electronics, switch boxes, sensor cable extensions, etc., at any time, without loss of accuracy, and without any need to recalibrate anything. This key feature prevents inadvertent - and often unrecognized - measurement errors inherent in the use of instruments and sensors which must be calibrated and used only as "matched sets".

Brief  PL SYSTEM specifications :

All PL SYSTEM sensors and electronics are factory compensated/calibrated, and are delivered complete, ready for use. The main system elements are Type PL sensors, electronics, and accessories, briefly described below :

Type PL Sensors include a very stable, platinum resistance temperature detector (RTD) and selected compensating resistors, sealed in a stainless steel housing. A cable and a connector complete the assembly.  Standard Type PL Sensors are available in three types of stainless-steel housings (304, 316, and Teflon-coated 316), housing lengths from 3 inches to 24 inches, a choice of two cable types, and cable lengths from 3 feet to 10 feet. Many other configurations are available on special order.

Type PL sensors are :

Sensor accessories include switch boxes for multi-sensor applications, sensor mounting adaptors, and sensor cable extensions.

PL SYSTEM electronics are designed for long-term stability and reliability. Their unique, patented circuit converts the sensor reading to a linearized voltage signal, calibrated to 10 millivolts per degree (C or F). This signal is available for control, recording, and monitoring, data acquisition, and data logging. It is also used as the input for digital display if applicable. The circuit eliminates the effects on the output of series resistances interposed between the sensor and the electronics, such as the use of sensor cable extensions or connector contact resistances, even if these resistances are unbalanced and variable. Connectors and interconnecting sensor cables need not be made from any special materials, as is the case with thermocouple systems. This key feature eliminates all errors due to sensor installation and wiring, and allows the use of very long sensor cable extensions. Computer-matched and tested components are used in the production of PL SYSTEM electronics to minimize signal noise and ambient temperature effects.

Standard electronics models include :

Electronics accessories include the PL-100 Calibrator, a compact but highly stable and accurate resistance standard which simulates the Type PL sensor characteristics at the two standard PL SYSTEM electronics calibration points:  0.00C (+32.00F) and +100.00C (+212.00F), The PL-100C can be used to conveniently verify, and if necessary, reset the calibration of all PL SYSTEM electronics, in the lab, on the production floor, or in the field.

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PL SYSTEM Applications

Some typical applications where the STOLAB PL SYSTEM is being used successfully are listed below; there are many others.

The PL SYSTEM makes a excellent replacement for : Return to Index

Ordering Information


All STOLAB products are sold and shipped directly from our factory in Hudson, MA, USA. Most standard PL SYSTEM items are in stock for immediate delivery - contact us for current prices and availability.

Application Help


We have over twenty five years of experience helping our customers to apply the STOLAB PL SYSTEM to many different temperature measuring needs. Contact us to discuss your requirements, and we will help you determine the best choice of equipment. Listed below are some of the parameters which may affect the choice :

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"STOLAB", " STOLAB PL SYSTEM",  "TYPE PL sensor"  are Stow Laboratories Inc's trademarks

Stow Laboratories Inc reserves the right to make changes to this publication without notice. This publication is for information only, it is not an offer to sell;  no guarantees of suitability for a particular use are offered or implied. Receipt of this information does not constitute a "sales presence" by Stow Laboratories Inc in the recipient's state or jurisdiction for sales tax or other purposes. Orders for STOLAB products are accepted only at Stow Laboratories'  location in Hudson, MA, and are governed by the laws of the Commonwealth of Massachusetts.

Copyright 1996-8, STOW LABORATORIES INC, All rights reserved