Document 9162
Manual - ST5484E 2-Wire Seismic Vibration Transmitter
Page 2 of 7
Rev. T (Oct 2013)
3. Wiring
The ST5484E is connected like any other loop powered transmitter. The following is a summary based on area designations.
CAUTION:
Use of a high speed torque screwdriver may cause damage to terminal blocks.
3.1 General
Connect the field wiring in accordance with the appropriate portion of Figure 1, which illustrates both single- and multiple-
transmitter loops.
The ST5484E transmitter requires a minimum of 11 VDC for proper operation. This is the minimum voltage required at the
transmitter (not the power supply), after all other voltage drops across field wiring and receiver input impedance have been
accounted for with the maximum 20mA of loop current flowing. The minimum loop power supply voltage required is
therefore 11 VDC plus 1 volt for each 50 ohms of total loop resistance.
Example:
Component
Resistance
Signal wiring
10 ohms
DC Input Impedance of receiver
250 ohms
TOTAL LOOP RESISTANCE
260 ohms
Minimum supply voltage = 260 (1V/50 ohms) + 11V = 16.2 VDC
The maximum loop power supply voltage that may be applied is 30 VDC. The maximum loop resistance (R
L
) is calculated by
the equation:
R
L
= 50 (V
S
- 11) ohms
Example:
R
L
= 50 (24 - 11) = 650 ohms for 24 VDC loop supply.
Figure 1