Micronics
U1000MKII-FM User Manual
Issue 2.0 June 18
Page 13
5.7 Pulse Output connection
The isolated pulse output is provided by a SPNO/SPNC MOSFET relay which has a maximum load
current of 500mA and maximum load voltage of 48V AC. The relay also provides 2500V isolation,
between the sensor’s electronics and the outside world.
The pulse output is available at the White and Green wires. Electrically this is a volt, or potential free
contact, and when selected as a low flow alarm is configurable NO/NC.
5.8 Current Output (If fitted)
The isolated 4-20mA is a current source and can drive into a maximum load of
620Ω.
The 4-20mA current output is available at the Red and Black wires.
The polarities are shown Page 12 Figure 8.
The alarm current due to a flow outside the range specified or due to a loss of signal is set at
3.5mA.
5.9 Modbus Connections (if fitted)
A lead is provided for the Modbus connections that plugs into the electronics assembly near the
power cable entry. The Brown is the +ve bus wire and the Black is the
–ve bus wire. Both White
wires go to ground.
Modbus Connector Cable Part - Binder 99-9210-00-04 (Front View)
For reliable operation of a Modbus network the cable type and installation must comply with
requirements in the Modbus specification document “MODBUS over Serial Line Specification &
Implementation guide V1.0”.
5.10 Cable Screen
For full immunity to electrical interference the screen of the power/pulse output cable and modbus
cable should be connected to Earth.
