Getting Started Guide Manual

Getting To Know Storm 3

Digital I/O

The Digital I/O connections can be conﬁgured independently as inputs or outputs. In input mode,

the signal has an internal pull up resistor of 47K Ohms. This allows a switch closure to ground to

activate the input. It can also be driven using normal 5 volt logic levels. Each port can also be set

up as a counter input for applications such as a tipping bucket rain gauge. As an output, a100-Ohm

protection resistor limits the drive capability. The output will still be about 4.0 volts with a load of

10.0mA or less.

SDI-12

The SDI-12 port operates as a “Master”, is V1.3 compliant and compatible with standard SDI-12

sensors. SDI-12 sensors have a minimum of three wires, which are +12V, Data, and Ground. If

connecting several SDI-12 sensors to the system, then an external bussed terminal strip may be

helpful. The +12Vout excitation grouped with the SDI-12 connections is active any time power is

applied to the unit. It cannot be turned off. There are two internally connected ground connections

for convenience, as some sensors have both a ground and a shield wire. In some cases, the shield

wire from the sensor should be connected to the case shield connection point provided.

Power Connection

The Power input uses a separate 2 position connector so the power can be disconnected

individually.

USB

Two USB-A connectors and one mini-B are provided, allowing direct connection to an external

device such as a Wi-Fi adaptor, laptop, tablet, or USB ﬂash drive. USB ﬂash drives can be used to

download data, save or load conﬁguration ﬁles, and load ﬁrmware updates.

Ground Lug

Proper shield or earth grounding should be used to protect the equipment from exposure to ESD

and other induced interference.

Wi-Fi Button

The Wi-Fi button can be gently pressed to activate the Wi-Fi signal (this is a capacitive button and

therefore may not work if using gloves). The USB Wi-Fi adaptor must be plugged into one of the

USB Host ports for the Wi-Fi button to work properly. The Active LED will turn on for a couple of

seconds when the button is successfully pressed. Wi-Fi adaptors power off automatically after three

minutes of inactivity.