Common Errors When Connecting Transducers - Intab PC-Logger 2100 User Manual

3.5

Common errors when connecting transducers

1) Ground Loops
Two bare wire thermocouples are soldered to the same metal object. A ground
loop results because "Gnd" of both channels are connected to "-".
The loop can be followed along the line: Gnd(1) - negative side of T/C(1) - metal
object - negative side of T/C(2) - Gnd(2) - Gnd(1). (All Gnd:s are the same
electrical point)
Solution 1: Disconnect one of the jumpers between "-" and "Gnd".
Solution 2: Isolate T/C tips electrically from object.
Solution 3: (The best) Connect as in 3.4.1. : 1)
2) "Floating" signals with no Gnd reference :
A common battery is connected between "+" and "-" of a channel. There is no
connection to "2100" Gnd.
Solution : Place a jumper between "-" and "Gnd" of the terminals!
Page 18
INTAB Interface-Teknik AB, Sweden