Vaisala HMP240 - Manual (Page 111)

HMP240
M210300en Appendix 3: Digital current loop module
109
Specifications
Galvanic isolation 1500 VAC/DC max. (1 min)
Loop supply voltage 40 V max.
Loop supply current 20 mA nominal
must be current limited
Operating loop voltage requirement 4 V/each transmitter (TX+/TX-)
on the loop
2 V/each receiver (RX+/RX-)
on the loop
Loop current 12...30 mA (space)
0...2 mA (mark)
30 mA max.
Connections Berg sockets
on the main board screw terminals 0.5 mm² wires,
stranded wires recommended
Assembly plug-in module
Board dimensions 40 x 28 mm
Operating mode half duplex
(single or dual pair wiring)
Network:
network type serial daisy chain
cable type twisted pair
line length max. 1000 m (3000 ft)
number of devices 6 devices on line (single loop)
9 devices on line (dual loop)
data speed 4800 baud max.
operating mode polling mode
isolation voltage proof 250 VAC (1 min)
Operating temperature -40...+60 °C
Storage temperature -40...+70 °C