Chapter 4 – Limit Controller
TestEquity 1007S Temperature Chamber
Page 4-1
Chapter 4 - Limit Controller
Introduction
The EZ-Zone Limit Controller is a protection device. It turns the chamber OFF if the workspace
temperature exceeds either a high temperature or low temperature limit. You can set these limits
to correspond to the maximum and minimum temperature that your test sample can safely
withstand. This provides protection against someone setting the Temperature Controller to a
temperature that is unsafe for the test sample. It also provides protection in the unlikely event of
a chamber system component failure. The Limit Controller has its own temperature sensor
(thermocouple) and functions completely independent of the Temperature Controller.
This section provides a brief overview on how to operate the Limit Controller. For more detailed
instructions, see the “EZ-Zone User’s Manual”.
!
CAUTION:
The “EZ-Zone User’s Manual” is a general manual and is written by the
manufacturer, Watlow, for a wide variety of applications and configurations.
Not all features or functions are applicable. Only the capabilities of a model
PM6L1AJ-AAAABAA are applicable.
!
CAUTION:
The EZ-Zone Limit Controller has been properly configured by TestEquity to
match the chamber’s system requirements. Improper modifications to these
setup values can result in unreliable and unsafe operation. Do not attempt to
modify the setup values, unless you thoroughly understand what you are
doing. The correct values are documented in the “EZ-Zone Limit Controller
Setup Parameters” section of this manual.
!
CAUTION:
Always verify that the Limit Controller’s high and low limits are set to
temperatures that are appropriate for your test sample.
!
CAUTION:
If your test sample is energized, it may be capable of raising the workspace
temperature beyond safe limits. This could occur if your test sample exceeds
the live load rating of the chamber or if the chamber’s refrigeration system
fails. This chamber has a set of contacts that can be used to remove power to
your test sample if the Limit Controller’s temperature limits are exceeded.