WIRELESS MODULES WITH POWER CONTROL CIRCUITS FOR HEAT TRACE SYSTEM

摘要

A heat trace system heats (or maintains the temperature of) vessels of a piping system. Heat trace cables are connected to power control devices in respective wireless modules such that when the power control device in a wireless module is on, the heat trace cable connected to that wireless module conducts current, and thereby heats the vessel contacting the heat trace cable. The wireless module receives control commands for controlling its power control device wirelessly from the main power distribution and control system via a wireless communication network. A wireless module can include a sensor, where the wireless module report backs conditions sensed by the sensor to the main power distribution and control system via the wireless network. The main power distribution and control system can use that information in its control loops to control the switching of the power control devices in the wireless modules, to thereby control whether the associated heat trace cable conducts current or not, to thereby control the temperature at the vessel that is heated by the heat trace cable.

主权项

1. A heat trace system for heating vessels of a piping system, the heat trace system comprising:
a main power distribution and control unit that comprises:
an electrical power source;a wireless communication gateway;a front-end controller in communication with wireless communication gateway; a plurality of heat trace cables, wherein each heat trace cable is adjacent to a vessel of the piping system; and a plurality of wireless field devices, wherein each of the plurality of wireless field devices comprises:
a power control device having an input connected to the electrical power source of the main power distribution and control unit, and having an output connected to an associated heat trace cable of the plurality of heat trace cables, such that when the power control device is ON, the associated heat trace cable conducts current from the electrical power source of the main power distribution and control unit;an RF module for communicating with the wireless communication gateway of the main power distribution and control unit via a wireless communication network; anda field device controller in communication with the RF module and the power control device, wherein the field device controller is for controlling the power control device based on control data sent from the front end controller of the main power distribution and control unit via the wireless communication network to the wireless field device and received by the RF module.