Sullair DMD Series, User And Service Manual

Page: 31 / 46

Section 5
31
DMD MODULAR REGENERATIVE DRYER
STARTUP AND OPERATION
5.1 INTIAL STARTUP
Ensure a suitable supply of compressed air between
60 psi g and 230 psi g pressure is available and
check that the dryer cannot be overflowed. Inlet
temperature must be between 40°F to 120°F at all
times.
IMPORTANT NOTE
Ensure all valves are opened and closed gradually.
Proceed as follows: (Refer to Figure 3-2 )
5.2 WITHOUT THE BY-PASS
LINE
Close inlet and outlet valves.
Introduce air to the dryer by opening the inlet valve
slightly, wait for the dryer to fully pressurize then fully
open the valve.. Allow dryer to fully pressurise, then
gradually open the outlet valve.
Turn on the ON/OFF switch at the bottom of the
dryer. The green LED on the panel will illuminate and
the dryer will start cycling in 10 seconds. The mini-
PLC screen shows the operations at that moment.
The dryer is now on stream.
5.3 USING THE BY-PASS LINE
With the inlet and outlet valves closed and the by-
pass valve open, introduce air to the dryer by
opening the inlet valve slightly, wait for the dryer to
fully pressurize then fully open the valve.
Allow the dryer to fully pressurise, then open the
outlet valve while simultaneously closing the by-pass
valve.
Turn on the ON/OFF switch at the bottom of the
dryer.The green led on the panel will illuminate and
the dryer will start cycling in 10 seconds. The mini-
PLC screen shows the operations at that moment.
The dryer is now on stream.
5.4 NORMAL OPERATION
Following the start-up procedure the operation of the
dryer is fully automatic and requires no further
attention until shut down.
The green ‘power on’ LED and the green ‘correct
operation’ LED should be illuminated continuously.
The dryer contains two desiccant chambers, while
one chamber is drying the compressed air
(adsorption), the other chamber is simultaneously
undergoing regeneration (desorption). At a
predetermined time both exhaust valves close and
repressurisation begins. Every two and a half
minutes the chambers are reversed in function, this
is the changeover point. Changeover is
characterised by an immediate venting of
compressed air from the chamber entering
regeneration.
The dryer can be shut down at any point in its cycle
and when restarted will enter an automatic
repressurisation stage. After repressurisation the
cycle will commence at the point at which it stopped.