PAGE 11
SENSO
RS AN
D INS
TRUME
N
TATIO
N F
OR MAC
HINE
CON
DITIO
N M
ONIT
ORIN
G
Wiring
BFD+ operates from a standard 2-wire, 4-20mA loop. If using a loop powered unit, attach the positive (+) input
from the power supply to Pin A on the sensor and the negative (-) input from the power supply to Pin of the
sensor.
Figure 8
– Loop-Powered Wiring Figure 9 – Loop-Powered Wiring with DC Source
If using a standard DC power supply, install either an ammeter and/or load resistor in line with the output.
The resistor will generate a DC voltage that is proportional to current by:
V
IR
If R
ohms and I
mA then V
VDC
500
6
3
,
Note:
- Resistor value must be less than: (Vsupply
– 12) x 50.
- For integral cable sensors: RED wire is positive, BLUE wire is negative.
- For flying lead sensors: RED wire in positive, BLACK wire is negative.
