ThermalRate™ System

How to Install

Low-cost installation is a major advantage of the ThermalRate™ System. There is no contact with the line, and no modification of the line is required. No line outage is required for installation or calibration. The TRM Sensor may be installed on a mast at the substation, on a separate pole, or on an existing transmission structure. It is positioned at about the line's minimum clearance limit and oriented in the same direction as the line in order to see the same weather conditions as the line itself under full rating current. The Sensor has an aluminum mounting bracket which can be drilled as needed to bolt it to either a mast or arm.

Click here to download 115 kV steel pole typical installation drawing
Click here to download 230 kV lattice tower typical installation drawing

ThermalRate™ Sensors are placed in locations along the line that will result in an accurate calculation of the line rating. Line rating is proportional to the weather conditions along the line, so the TRMs should be placed in locations where they will see the same average weather as the line. 
When determining appropriate locations for the TRMs, it makes sense to consider locations that are easily accessible and locations which have AC power nearby (although solar power is available). The plan and profile drawings of the line give valuable information as to where to place TRMs. In general, TRMs are placed near the critical line sections (river crossings, long spans, vehicle access underneath).

The number of TRMs required depends on how the weather changes along the route. Weather changes with distance, mainly due to geography and to weather patterns. A single monitor can be used to accurately calculate the rating of the line up to a certain distance away.

For convenience, the TRM Controller can be mounted close to the ground. 
The chassis has flanges so it can be bolted or lagged to the side of a building, pole, or tower. A cable is supplied to connect the TRM Controller to the TRM Sensor.