Users Manual & Installation Guide

PV- 1800: Power supply module with GSM MODEM

Analogue inputs (CN5)

The PV-1800 has 8 isolated analogue inputs accessible in a 10pin box header (CN5). Beside these inputs, there is also a +3.3V isolated voltage with common ground reference as the analogue inputs. This voltage can be used to power external conditioning circuitry.

Depending on the model – see section ordering codes – each input will have a full scale of 2.5V, 5.0V, 10V, or 20mA. The table shows the connector layout:

 

Pin no

 

Name

 

Pin no CDB-9F

 

 

1

 

Analogue GND

 

1

 

 

 

 

 

 

2

 

Analogue input#7

 

6

 

 

3

 

Analogue input#6

 

2

 

 

4

 

Analogue input#5

 

7

 

 

5

 

Analogue input#4

 

3

 

 

6

 

Analogue input#3

 

8

 

 

7

 

Analogue input#2

 

4

 

 

8

 

Analogue input#1

 

9

 

 

9

 

Analogue input#0

 

5

 

 

10

 

+3.3V Isolated

 

 

 

￿ ￿ ￿ ￿ ￿

+. ￿ ￿

￿￿1#+￿@￿5￿￿￿￿=&￿6

The input circuitry looks like this:

&￿)￿￿ ￿￿ ￿￿<

￿￿ ￿￿￿)@

￿! %! ￿￿￿￿￿

￿￿￿(￿￿

The analogue inputs on PV1800 are factory configured by choosing proper values for R1 and R2. In the table the values are shown for the different models. The input resistance is 1M￿ on all voltage input channels. The software interface is explained in section PV-1800 register interface.

Configuration

R1

R2

0

- 2.5V

0 ohm

1 Mohm

0

- 5 .0V

449 Kohm

449 Kohm

0

- 10.0V

741 Kohm

246 Kohm

0

- 20mA

0 ohm

125 ohm

Differential measurement

The analogue inputs can two by two be used for differential measurement. Inputs, which can make up a pair, are defined in the software. One of the wires, in each pair, is inside the ADC connected as a ‘negative’ input; the other as a ‘positive’ input. The common mode voltage on the ‘negative’ input must not exceed 0.5V in a 0 – 2.5V configuration and 1V in a 0 - 5V configuration. The combinations of the actual inputs used for differential measurement are shown in section - PV-1800 register interface. Also here it is described which input that is used as the ‘negative’.

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Micro Technic PV-1800 user manual Analogue inputs CN5, Differential measurement, Pin no Name, Configuration