Vectronics VEC-1500K - Manual (Page 20)

15
temperature regulation of a transformer powered bench station, but they get
small jobs done quickly without need for running extension cords or removing
equipment from remote locations. Another type of alternative iron, the trigger-
operated soldering gun, has been around for many years. These days, battery-
powered versions are especially popular.
Butane Iron
Battery-Powered Gun
Battery-Powered Iron
High-Capacity Irons:
High-output irons are characterized by powerful heating
elements (100 watts or more), elevated tip temperatures (up to 1000-degrees F),
and massive tips. These "Big-Bertha" irons are especially useful for heating
large surface areas, heavy-gauge wiring, and certain types of RF-cable coaxial
connectors. Most shops and labs have one tucked away for special jobs. High-
output irons can inflict severe burns very quickly, and must be handled with
plenty of respect!
High-Capacity Iron
Other specialized resistance-soldering systems are sometimes used for connector
installation--especially in manufacturing. Resistance soldering units consist of a
powerful low-voltage high-current transformer connected to a special clamp-on
hand-tool. When the hand-tool is clamped on, it literally turns the entire metallic
part into a heating element! Heating is uniform and fast with these systems.
How Soldering Irons Work: A soldering iron has two jobs. First, it generates
thermal energy (or heat) by means of a heating element. Second, it stores up and
transfers that heat to a solder connection via the tip. Prior to contact with a
solderable connection, the iron pre-heats well above the melting temperature of
solder (typically 600-800-degrees F). As it heats, a substantial reservoir of
thermal energy becomes stored in the barrel and tip. Upon contact, an energy
exchange takes place that simultaneously heats up the solder joint and cools
down the iron. Most of the heat required to complete an average connection
comes from stored energy alone. However, the element assists by pumping new
thermal energy into the tip to slow its rate of cooling. Once tip contact is
broken, the element immediately begins to reheat the iron, restoring an energy
reservoir in preparation for the next connection.