Laurel Electronics LTE: Ethernet & 4-20 mA Output RTD Transmitter for Pt100, Cu10 and Ni120 RTD Input - Manual (Page 4)

LAUREL ELECTRONICS INC., 3183-G Airway Ave., Costa Mesa, CA 92626, USA • Tel 714-434-6131 • www.laurels.com 4
RTD Hookup
In 4-wire hookup, different pairs of leads are used to apply the
excitation current and sense the voltage drop across the RTD,
so that the IR drop across the excitation leads is not a factor.
In 3-wire hookup, the transmitter senses the combined voltage
drop across the RTD plus two excitation leads. It also senses the
voltage drop across one excitation lead, and then subtracts twice
this voltage from the combined total. This technique effectively
subtracts all lead resistance and compensates for ambient
temperature changes if the two excitation leads are identical.
In 2-wire hookup, the transmitter senses the combined voltage
drop across the RTD and both lead wires. The voltage drop
across the lead wires can be measured by shorting out the RTD
during transmitter setup, and this voltage is then automatically
subtracted from the combined total. However, changing resist-
ance of the lead wires due to ambient temperature changes will
not be compensated.
Ordering Guide
Create a model a model number in this format: LTE20P385C
Transmitter Type LTE Laureate 4-20 mA & Ethernet Transmitter
Main Board 2 Standard Main Board
Power 0 Isolated 85-264 Vac
1 Isolated 12-32 Vac or 10-48 Vdc
2 Power over Ethernet (PoE)
P385C Pt100 DIN RTD, -202°C to 850°C
P385F Pt100 DIN RTD, -331°F to 1562°F
P392C Pt100 ANSI RTD, -202°C to 631°C
P392F Pt100 ANSI RTD, -331°F to 1168°F
N672C Ni120 RTD, -100°C to +260°C
N672F Ni120 RTD, -148°F to +500°F
C427C Cu10 RTD, -100°C to +260°C
C427F Cu10 RTD, -148°F to +500°F RTD Input
Note: The same signal conditioner board can be user configured for all RTD types
listed and °C or °F, as well as for resistance measurement.