Energy Management; Overview; Developing A Purge Control Strategy; Using A Manual Switch For Purge Control - Beko DRYPOINT ACC 46 Instruction Manual

Overview

Section 7: Energy Management
Regenerative dryers must expel a portion of the process air
in order to free themselves of accumulated moisture. During
periods of low air demand, however, this air loss is not
necessary and is therefore undesirable. In many cases, the
compressor runs almost continuously in order to keep up with
the dryer's purge loss.

Energy Management

Management feature that allows the purge to be shut
during periods of low or no demand. The dryer controller
employed to shut
purge function of the dryer, therefore eliminating any air loss
Overview
from the dryer.
Regenerative dryers must expel a portion of the process air in order to free
Devel o ping a p urge control str ateg y
themselves of accumulated moisture. During periods of low air demand,
however, this air loss is not necessary and is therefore undesirable. In many
cases, the compressor runs almost continuously in order to keep up with the
In order to utilise this function, the operator must provide a
dryer's purge loss.
switching system that provides acceptable logic to indicate to
the dryer that there is little or no air demand. On the following
All dryers are equipped with an Energy Management feature that allows
pages, some examples of commonly used switching systems
the purge to be shut off during periods of low or no demand. The dryer
are provided in ascending order of complexity.
controller is fitted with a set of field accessible contacts, that can be
employed to shut off the solenoid valves which control the purge function of
the dryer, therefore eliminating any air loss from the dryer.
Using a ma n ual swit ch for purge control

Developing a Purge Control Strategy

The simplest of arrangements, a manual switch, may be
employed to shut the purge
the dryer is not being used. Commonly used on point of use
In order to utilize this function, the operator must provide a switching
system that provides acceptable logic to indicate to the dryer that there
systems. For example, if the dryer is only used to supply air of
is little or no air demand. On the following pages, some examples of
commonly used switching systems are provided in ascending order of
the dryer will only be required when the machine is in use and
complexity.
may be shut either manually or possibly via extra contacts
provided in the machine's on/
It is extremely important to understand that the purge may

Using a Manual Switch for Purge Control

only be shut during periods of low or no demand. This
feature, if used otherwise, can result in permanent damage
The simplest of arrangements, a manual switch may be employed to shut
to the desiccant beds resulting in loss of drying capacity
the purge off when the air downstream of the dryer is not being used.
and possibly mechanical failure. The cartridges must not be
Commonly used on point of use systems. For example, if the dryer is only
allowed to become fully saturated at any time.
used to supply air of an appropriate dryness to a specific machine or
application, the dryer will only be required when the machine is in use and
may be shut off either manually or possibly via extra contacts provided in the
machine's on/off switch.
It is extremely important to understand that the purge may only be shut off
during periods of low or no demand. This feature, if used otherwise, can
result in permanent damage to the desiccant beds resulting in loss of drying
capacity and possibly mechanical failure. The cartridges must not be allowed
to become fully saturated at any time.
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dryers are equipped with an Energy
the solenoid valves which control the
when the air downstream of
switch.
Fig 7. 1 M anu al switch p urge c ontro l (LED Controller)
Pin 2
1
2
Pin 1
3
(Puts out
+5 VDC
signal)
Signal Out to Switch
The following schematic (Fig 7.1) offers an overview of the devices
Signal Back
mentioned as they might be connected for use in controlling a dryer's
* Normally Closed, open to turn purge off
purge function. Please note that specific details differ between device
manufacturers, so in all cases the manufacturer's specifications should be
adhered to.
Fig 7.2 Ma nual switch p urge c ontro l (DMC Controller)
Fig 7.1 Manual switch purge control
Signal Out to Switch (+24 VDC)
Signal Back
Signal Out to Switch
* Normally open, close to turn off purge
Heatless Desiccant Dryers |
LED Controller
N.C.*
Manual Switch
(Field Installed)
Pin 1
1
3
2
Pin 2
Controller
N.O.*
Manual Switch
(Field Installed)
Instruction Manual
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