With helpline, readers have a chance to solve problems that crop up in their heat processing applications.

Question: Our company currently is working on a project that involves detecting body heat or movement under water. Could you please suggest the type of sensors we can use for this application? Also, how much do they cost? - B.S.

Answer: You can use passive infrared (PIR) motion detectors that can detect heat from humans or pets covering 900 ft2 and up. There are many vendors out there. Look at hubbel-canada.com, infrared-center.com, infraredsolutions.com, etc. Use NEMA 6P enclosures and cables for underwater applications. Try enclosuresonline.com or stahlin.com for enclosures and efector.com or leviton.com for cables and connectors. Or, use wireless sensors (intermatic.com). - Stevanus Yani, yani@mindspring.com.