KROHNE VFM 3100 EN - Manual (Page 7)

1.1.3. Standard Specifications
Table 1.
7
Item Specification
Process Temperature Limits -20 and +430 °C (0 and 800 °F) (a)
Ambient Temperature Limits -40 and +85 °C (-40 and +185°F)
Power Supply Requirements:
Supply Voltage Limits 12,5 and 42 V dc
Supply Current 22 mA dc
Product Safety Specification Refer to instrument data plate for type of certification and
observe aplicable wiring requirements. Electrical certifications
and conditions of certification are listed on page 8.
Flow Rate Requirements Rd = 5000 minimum: Automatic compensation for the
non-linear behavior of vortex shedding in the Rd range
5000 to 20000 is built into the VFM 3100.
This compensation requires the user to input values
for the flowing density and viscosity.
Static Pressure Limits Full vacuum to pressure rating of mating flanges
with maximum operative limit of 10 MPa (1500 psi:
100 bar or kg/(cm
2 ) at 24°C (75°F).
VFM 3100 Output
Analog 4 to 20 mA dc into a maximum of 1450 ohms depending
on power supply (refer to graph in Figure 12).
Digital (HART) Digital signal conveyed at a 1200 baud transmission rate.
HART protocol.
Scaled Pulse Isolated 2 wire „contact closure”. Pulse rate
(0 to 100 Hz) proportional to volumetric flow rate.
Scaled Pulse Output Specifications • Isolated 2-wire contact-closure
• Applied voltage limits:
12.5 Vdc minimum
42.0 Vdc maximum
• Maximum „ON” state voltage drop: 0.5 Vdc
• Maximum „ON” state current: 250 mA
• Update rate: 4 Hz
• Maximum „OFF” state leakage current:
0.10 mA @ 12.5 Vdc
0.25 mA @ 24.0 Vdc
0.42 mA @ 42.0 Vdc
• 250 mA short circuit protected
• Reserve polarity protected
Signal Output Combinations 2-Wire Hook-Up
4-20 mA and HART (1200 baud)
3-Wire Hook-Up
4 to 20 mA, HART (1200 baud) and Scaled Pulse
4-Wire Hook-Up
4 to 20 mA, HART (1200 baud) and Scaled Pulse
(a) Maximum temperature limit is a function of sensor type.