Vaisala HMP228 User Manual
Page 103
HMP228
M210282en-A
Appendix 5: Digital current loop module
97
5.
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