Product Overview

Pneumatic Control Manual 717.1
Remote Bulb Controllers Section
Product Bulletin T-8000
Issue Date 0883
© 1983 Johnson Controls, Inc.
1
Code No. LIT-7171280
T-8000
Proportional and Two-Position
Remote Element Controllers
The T-8000 Remote Element
Thermostat is designed for
applications which require the
sensing element to be located
where extreme conditions do not
permit controller mounting, or
where operational adjustments
to the controller would be
inconvenient. This high volume
(output) instrument is ideally
suited for installations that
require the controller to be
mounted on a local control
panel.
The thermostat can be made to
function as a direct or reverse
acting instrument by changing
position of the patented sliding
control port. Repositioning the
control port will also change
sensitivity on proportional
models and differential on
two-position models.
Operation
As the temperature at the
measuring element increases or
decreases, the liquid in the
element expands or contracts at
a linear rate. This will cause the
system of flexure levers to open
or close the control port. For a
direct acting instrument, the
sliding control port should be
positioned above the mid-point
on the slider rail. For a reverse
acting instrument, the slider
control port should be positioned
below the mid-point on the slider
rail. The rail is marked DA
(Direct Acting) at the top and RA
(Reverse Acting) at the bottom.
Moving the slider upward from
the mid-point on the rail
increases sensitivity and
decreases differential for direct
acting applications. Moving the
slider downward from the mid-
point on the rail increases the
T-8000 Remote Element Controller
(Element Not Shown)
Specifications
T-8000 with Cover Removed