Vaisala Hydromet Data Collection Platform - Manual (Page 25)

Chapter 2 __________________________________________________________ Product Overview
VAISALA_______________________________________________________________________ 23
3. One connector block for communication channels.
4. Two blocks for optional communication modules.
Single-ended (H-C or L-C) or differential (H-L) measurements can be
performed in the 10 measurement channels.
NOTE Each sensor in a basic setup has its own dedicated channel. Table 4 on
page 23 is to be used for reference purposes only.
Table 4 Analog Measurement Channels
Channels Pin Name Description
CH0, CH1, CH2,
CH3 24-bit ADC E 12 V/25 mA voltage excitation ON/OFF,
voltage can be measured.
OR: 100
A/1mA current excitation.
H Analog input (High)
L Analog input (Low)
C The pin has been connected to ground
(GND) via a 10
 resistor so that the
current can be measured.
CH4, CH5, CH6,
CH7 24-bit ADC E 100 A/1 mA current excitation
H Analog input (High)
L Analog input (Low)
C Common return and reference level for
voltage measurements via the channel's
own E-, H-, and L-pins. The pin has been
connected directly to ground.
CHA, CHB Suitable
for fast-changing
input signals 12-bit
ADC F Frequency input
E 0 ... 12 V/20 mA adjustable excitation
voltage, can be measured.
H Fast analog input (High)
L Fast analog input (Low)
C Common return (Analog ground)
Table 5 Power Channels
Pin Name Description
GND Ground
SDI-12 SDI-12
GND Ground
+ExtDC 8 ... 30 VDC