Emerson Rosemount 8600 Series, Reference Manual, Page: 43 / 130

35 Rosemount 8600 Vortex Flow Meter
Reference Manual
May 2019
Installation
00809-0100-4860, Rev BF
To ensure proper operation, wiring should be:

24 AWG or larger.

Less than 5000 ft. (1500 m) in length.
Note
If an Emerson Smart Wireless THUM ™ Adapter is being used with the Rosemount 8600
flowmeter to exchange information via the Wireless HART protocol, an additional 2.5 Vdc is
dropped in the connected loop. This is because the THUM is wired in series with the transmitter.
Please use the following formula to calculate the maximum loop load resistor.
Loop Load Calculation: R
loop(max)
= (V
ps
– 10.8 – 2.5) / 0.024
Where:

R
loop(max)
= The maximum value the loop load resistor can be.

V
ps
= Power Supply Voltage.

10.8 = minimum terminal voltage “V
terminals
” in Vdc.

2.5 = Maximum voltage drop across the THUM wireless adapter.

0.024 = maximum transmitter current in Adc.
Analog output
The flowmeter provides a 4–20 mA dc isolated current output, linear
with the flow rate.
To make connections, remove the FIELD TERMINALS side cover of the electronics housing. All
power to the electronics is supplied over the 4–20 mA signal wiring. Connect the wires as
shown in
Figure 3 - 14 on page 37 .
Pulse output
Note
Remember when using the pulse output, all power to the electronics is still supplied over the 4–
20 mA signal wiring.
Gage number A.W.G.
Ohms per 1,000 ft (305 m) at 68 °F (20 °C)
equivalent
14 2.525
16 4.016
18 6.385
20 10.15
22 16.14
24 25.67