In the Market for an Industrial Annunciator? Here's a Guide to Help

Alarms and Annunciators

Annunciators are found in industrial control rooms, boiler rooms, power substations and just about any type of process control operations room where the process conditions need to be closely monitored and where constant status indication is important.

Here is an outline for the primary selection criteria for an integrated logic alarm annunciator:

Chassis

• Panel mount
• Surface mount
• Rack mount

Alarm Points

• How many alarm points do you have? Annunciators break down alarm points by "cell" and you call out the number of cells based on the layout desired. For instance, a 1x4 would be 1 annunciator cell tall by 4 cells wide. 

Pushbuttons (and Location)

• Occupying bottom right module cell space
• On the bottom right trim of the chassis
• Located remotely

The Available Panel, Box or Cabinet Space Available

• Dictates how alarm points and pushbuttons are arranged.

Networkable or Stand-alone?

Configuration via software?

Event recording?

Do you need electrical outputs?

• Audible and visual signals: horn, beacon, bell
• Common Trouble Alarm (CTA) Relay: notification of any alarm within the system (commonly used for remote beacon or dial-up) 
• Group CTA functions: for critical and noncritical groups 
• Auxiliary Contact Repeat Relay: individual repeater output per input 
• Reflash Alarm Relay: alarm counter 

Field contact voltage?

Source voltage?

Alarm type grouping? 

For a detailed annunciator selection guide (courtesy of RONAN Engineering) visit this annunciator selection guide link.

Refractory Metallization

Fabricated by refractory metallization

High-temperature refractory metallization is the only solution for some packaging applications. Tungsten and Moly-Manganese metallizations have higher adhesion to the substrate than thick-film metallization. This makes it the ideal process for hermetic packages, brazed lead frames and packages requiring high operating temperatures. These metals can be screen printed, sprayed or hand-painted onto alumina oxide or beryllium oxide substrates. Patterns can be plated with gold and nickel or gold alone. Once gold plated, these surfaces are solder-able and wire bond-able with aluminum or gold wire.

Batch furnaces are ideal for accurate brazing of small quantities and large. Kovar, stainless steel, copper and copper/tungsten as well as many other metals can be brazed to metallized ceramic. When the application requires, step brazing can be performed to combine several sub-assemblies into the final product.

For more information on hi-temperature refractory metallization contact:

Belilove Company Engineers

P.O. Box 55936
21060 Corsair Blvd
Hayward, CA 94545
Phone: (510) 274-1990
Fax: (510) 274-1999
E-mail: sales@belilove.com

Thermocouple Basics - Wire Type, Connectors, Construction

Industrial thermocouples, as the temperature sensor in a thermal system, are explained in the video below.

Seebeck Effect
(image courtesy of Wikipedia)

Thermocouple "Types", based upon standardized color designations is discussed, as well as thermocouple connectors, polarity and some aspects of construction (such as grounded vs. ungrounded vs. open tip).

Thermocouples are a fairly accurate, economic temperature sensor used in many industrial applications. They operate on the "Seebeck Effect" which is the phenomena of dissimilar metal conductors producing a measurable voltage difference between two substances.

Thermocouples are used widely in industrial thermal system design in industries such as power generation, primary metals, pulp and paper, petro-chemical, and OEM equipment.

For more information contact:
Belilove Company Engineers
21060 Corsair Blvd
Hayward, CA 94545
Phone: (510) 274-1990
Fax: (510) 274-1999
E-mail: sales@belilove.com

Thick Film Heating Elements: An Excellent Choice for Custom OEM Thermal Designs

Custom Thick Film
Heaters and Circuits

Thick film heating elements, originally designed for the automotive and military industries, are manufactured by depositing several layers of conductor, resistors and dielectric on to an insulator via a screen printing process. The dielectric is normally some type of glass or ceramic and provides electrical insulation for the screen printed heating tracks.

Thick film heating elements are almost always custom designed for OEM applications. They can be designed in all shapes and sizes, and have an ability to provide very high watt densities with excellent controllability. The largest markets for these heating elements are appliances, analytical instruments, automotive, semi-conductor, medical device, scientific and military equipment.

Because of their inherent low mass, and their ability to carry high watt densities, thick film heaters are very efficient and are an excellent choice where a rapid heat-up (response) is required.

Advantages of thick film heaters are:

• Watt-Density up to 175 watts per sq. in. 
• Operating Temperature to 500 deg C
• Low Profile
• Excellent Control
• Very uniform heat profile
• Temperature sensors can be included on the heater
• Custom heating profiles
• Very rapid heater response
• Vibration and shock resistant
• Very customizable shapes, sizes and wattages