20
CONTOIL
®
Electrical connections
Safety precautions
Disconnect from power supply. Before working on electrical installations, make sure that nobody can power up
the facility.
Pay attention to installation instructions for electrical devices:
• voltage, operation data
• maximum transmission length
• cable cross section, length
• ambient temperature, mounting position
Wiring diagram VZF and FZFA
our different output functions are available:
• Pulser for volume pulses with programmable pulse value (for external totaliser)
• Analogue current output 4...20 mA corresponding to flow rate
• Frequency output 0...100 Hz corresponding to flow rate
• Switching function (limiting value switch) specified by programmable upper and lower flow rates
Except for the analogue output function, any two of the remaining three functions can always be used simultaneously.
This results in two types of connection; the desired one must be set in the Parameter Menu.
• 1 potential-free digital output (Rel.1), freely parameterisable to one of the three functions mentioned below.
• passive current output, 4…20 mA (Analog), used to power the meter at the same time.
Pulse output
Frequency output
Switching output
Sensor area!
No cables, wires or other installation
material must be present in this area.
This can lead to incorrect measurements
and damage to the meter.
• 2 potential-free digital outputs (Rel.1+Rel.2), each freely parameterisable to one of the three functions mentioned below.
• the current output is not available here, but the power is provided via its terminals.
Pulse output
Frequency output
Switching output
Sensor area!
No cables, wires or other installation
material must be present in this area.
This can lead to incorrect measurements
and damage to the meter.
Current Output
Resistance R
L
= (U-5)V/0,0215 [
Ω
]
Exemple 24 V R
L
= (24-5)/0,0215 = 883
Ω
Solid state relay
R
ON
< 100
Ω
, R
OFF
> 10 M
Ω
U
max
< 48 V AC/DC, I
max
< 50 mA
Solid state relay
R
ON
< 100
Ω
, R
OFF
> 10 M
Ω
U
max
< 48 V AC/DC, I
max
< 50 mA
