Microtrac™
Document: UMDB007595.docm
Revision: B13
Created by: KB
Date: 17 Nov 2019
IPN: 3042830-B13
Source Location: C:\ePDM\ISLEng\products\db-microtracs4000\manuals\UMDB007595.docm
Page 10 of 26
User Ma
nual
Elevated Temperature & Thermal Shutdown
‘Duty Cycle’ refers to the length of time a track can run before overheating, and the following time
required to cool down. The duty cycle of the Microtracs 4000
™ depends on:
•
Track Material Thermal Conductivity (Aluminum, Brass = Good; Stainless = Poor)
•
Ambient Temperature
•
Track Load & Speed
•
Wet / Dry Operation
•
Heat Sinking
A track typically converts about 25% of the electrical input into motive mechanical power with the
remainder being converted into waste heat transferred to the environment outside the track. When run
continually at maximum power in a warm environment - up to 50 °C (120 °F), the tracks can heat up to
the maximum temperature within ½-hour. However, this does not represent normal operation. Typical
usage will include much starting and stopping for visual/NDT inspections and moderate loading for most
of a pipe run for pulling tether
– so reaching the thermal limit of the track is not expected to be a common
operational concern. When tracks are bolted to a chassis, it further acts as a heat sink to help cool the
tracks.
When a tracks internal temperature reaches 80 °C (175 °F) it will automatically shut down and wait until
its internal temperature drops below 70 °C (160 °F) before restarting. If the tracks are operating
underwater, such as in a flooded pipe, heat transfer is excellent, and the duty cycle may be considered
continuous
.
Note: Stainless steel tracks will require special consideration for cooling, as they
reach thermal shutdown sooner due to the extremely poor thermal conductivity of
the stainless steel itself.
