SRC 3000 - 8.1.1. Problems on the Two-wire

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Chapter 8. Troubleshooting in the Field
You discover problems with the installation in the field in a number of ways. The following four sections walk
you through how to deal with the most frequent scenarios.
8.1. Checking Power and Current Readings
In a healthy system you should see power and current readings for the two-wire path along these lines:
Idling
Heavy Usage (many stations
running)
Power
33-36V
31-34V
Current
0-3mA (no stations attached)
300-600mA
Tip
See Section 7.2, “Testing the Two-wire Path” [41] for instructions on how to do power and
current readings in the display of the Ranger Converter 3000.
Tip
When the Ranger Converter 3000 shows high current readings, always first disconnect two-
wire at the Ranger Converter 3000. Use the switches to do so (refer to Section 3.1.7,
“Connecting the Two-wire” [14]). If the high current disappears, the two-wire is the problem. If
the high current remains, the Ranger Converter 3000 has the fault.
To get a more precise idea of how your current reading should be, you should add the standby usage and
the usage for any running units, using these rules of thumb:
Standby Usage
When no valves are running, all connected stations will consume around 0.5mA each. This is not an
exact number and will vary by 20-30 percent in each direction - it's normal to see idle consumption in
the 0.4- 0.65mA range.
So, for example, 20 connected stations will consume around 8-13mA, and 100 units will consume some
40-65mA. Note that this will be true even if there is nothing connected to the white (output) wires of the
decoder. Each decoder all by itself draws 0,5 mA.
Active Stations
When active, any station, controlling a valve or master valve, will consume around 15 - 35mA.
This means that when running just one station or a master valve on a system with 96 connected units,
you may use around 115-140mA.
Note
These numbers are valid for an running with normal power settings - if you change the power
settings (as described in ???) the numbers will change - the higher power settings, the higher
current readings.
Here are a couple of practical scenarios and how to deal with them: