Industrial Wireless Modbus

Industrial Wireless
Precision Digital’s PDW wireless products give you a simple, straightforward way to get analog, discrete, or Modbus signals from where you have them to where you need them. Our wireless solutions range in complexity from simple point-to-point for wire replacement, to large-scale point-to-multipoint for connecting up to 32 individual field locations to a central base station. Wireless installations may be expanded or improved using an array of base station modules, additional wireless field units, and repeater units. The wireless survey tool kit can provide you with an accurate representation of wireless signal strength throughout your facility before you perform the installation.

Industrial Wireless Modbus

  • In its most basic form, the PDW90 consists of field units (up to 32) that accept 4-20 mA signals and transmits them wirelessly to a base station. The primary advantage of this system is how simple and economical it is to get multiple signals (not just 4-20 mA, also discrete (digital) and Modbus) from where you have them to where you need them – all without having to run wires!

    The wireless communication between the field units and the base station is bi-directional. That means you can send 4-20 mA, discrete and Modbus signals from the field units to the base station and also send completely different 4-20 mA, discrete and Modbus signals from the base station to the field units. For instance, the field unit could send a 4-20 mA signal to the base station corresponding to the level in a tank and the base station could send a 4-20 mA sig-nal to the field unit to control a valve.

    Field units are also equipped with four digital I/O that can each be independently programmed as an input or an output. A Loss of Signal warning is also available by connecting devices to the G and LS screw terminals.

    To indicate alarm situations in the field, the field unit can be equipped with an optional, field installable, two relays module. These relays are rated Form A (SPST) 5A and are controlled by the digital outputs on the base station.

    The base stations are available in configurations for 2, 6, or 16 I/O slots for a variety of field installable I/O modules. The available I/O modules are:

    • •Dual Analog Input
    • •Dual Analog Output
    • •Dual Relay Output
    • •Four Digital I/O

    The specified range between the base station and field units is 1 mile line-of-sight outdoor and 500 feet indoor and repeaters are available to extend the range. A low-cost wireless survey tool, Model PDA10, is available to test the signal strength of your application before you buy. And if the PDW90 system does not work in your application, you can return it for full credit!