|
2
Channel Counter (OWCTR2)
Description:
This 1-wire card uses the DS2423
IC to measure two counter/frequency channels. Each channel has
a 10K pullup resistor to +5V. It is expected that you connect
a dry contact between Common and the desired input channel or
you use an input voltage that varies between 0 and 5V. Examples
include a tipping bucket rain gauge, contact closure anemometer
and light sensor. If you have a "noisy" switch you may wish
to connect a capacitor between the input and common.
If the optional battery backup
is ordered, the device will count even during a power failure
(included with the tipping bucket rain gauge).
Card Type: 2
| Card Type |
Description |
| 2 |
2, 16 bit Modbus
registers (2, 16 bit counter channels) |
Connector CN2
(5-pin style) Pinout:
| Pin
Numbers |
Description |
| 1 |
Common or Ground |
| 2 |
Counter channel
1 |
| 3 |
Counter channel
2 |
| 4 |
Unused |
| 5 |
+5V Power Output |
Connector CN2
(6-pin style) Pinout:
| Pin
Numbers |
Description |
| 1 |
Common |
| 2 |
Unused |
| 3 |
Unused |
| 4 |
Counter channel
2 |
| 5 |
Counter channel
1 |
| 6 |
+5V Power Output |
OWconfig:
The "Type" must be 2 as described
above. The "Mode" must always be "Separate power".
Modbus Register
Information:
The device has two consecutive
Modbus input registers on the ICONIO board, one for each counter
channel. Each Modbus register value will count from 0 to 65534
and then, after 2 counts, wrap back to 0 again. The special
value, 65535, indicates that the card has failed.
Specifications:
| Parameter |
Specification |
| Temperature |
-40 to +85 C (-40 to +185F) |
| Input Impedance |
10K ohm |
| Power |
2 mA with both
contacts closed. |
| Debounce Time |
170-460 uS |
| Minimum
Pulse Width |
1 uS |
Schematic
and Parts List:
| Reference |
Part Number |
| CN1 |
Digikey 281-1451-ND |
| CN2 |
Digikey 281-1452-ND |
| D1 |
Dallas Semi DS9503P |
| D2, D4, D5 |
Digikey SA5V0ADICT-ND |
| U1 |
Dallas Semi DS2423P |
| R1, R2 |
Digikey 10KQBK-ND |
|
