Gardner Denver DEB Series Instruction Manual Download

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Legend

Item

Description

Standard Components

V1 & V2

Left & Right inlet valves, butterfly valve with
double acting actuator

V3 & V4

Left & Right purge valves, butterfly valve with
spring return actuator

V5 & V6

Left & Right depressurization valves, 2-way
solenoid valve

V7 & V8

Left & Right outlet check valves

V9 & V10

Left & Right purge check valves

V11 & V12

Left & Right inlet pilot valves, Namur mount,
dual solenoid

V13 & V14

Left & Right purge pilot valves, Namur mount,
single solenoid

V15

Repressurization valve, ball valve with double
acting actuator

V16

Repressurization pilot valve, Namur mount,
single solenoid

V17

Pilot air shut-off valve, ball valve

RV1 & RV2

Left & Right tower pressure relief valve

Purge air blower with TEFC motor

Blower intake filter

Pilot air filter, general purpose air line filter

Purge air heater

M1 & M2

Left & Right depressurization muffler

O1 & O2

Repressurization (flow control) orifices

PI1 & PI2

Left & Right tower pressure indicators (gauges)

PPS

Pilot Air pressure switch kit

PS1 & PS2

Left & Right tower pressure switches

PS3

Blower pressure switch

TI1 TI2

Left & Right tower temperature indicators (gauges)

TS1 &TS2

Left & Right tower temperature switches

TC1

Heater outlet thermocouples

TC2

Heater high limit thermocouple

TC4

Blower hi-limit thermocouple

Optional Dew Point Monitor

V21

Dew point transmitter isolation valve

DPT

Dew point transmitter with integral inlet filter and
outlet flow orifice

Figure 4.2

4.3 Operating Sequence Description
(see Figure 4.2)

A. Fixed Cycle - One Stage Regeneration (Standard)

(1) Left Tower Drying - Right Tower Regenerating

At the start of the drying cycle, both inlet valves
(V1,V2) are open. The right inlet valve (V2) is then
closed to isolate the two towers. Wet, compressed
air flows up through the left tower where it is
dried. The dry air exits the dryer through the outlet
check valve (V7).

Next, the right depressurization valve (V6) is
opened and the right tower is slowly depressurized.
Air exits through an exhaust muffler (M2).

Next, the right purge valve (V4) is opened and the
blower (B1) and heater (H1) are energized. The
heated air flows through check valve (V10), down
through the right tower, and exits through the right
purge valve (V4). The blower intake air is filtered
(F1) to keep dust and dirt from entering the dryer.
The blower (B1) and heater (H1) are de-energized
when the temperature at the bottom of the right
tower, as sensed by temperature switch (TS2),
reaches the design set point. This indicates the bed
has been fully heated.

Finally, the right purge valve (V4) is closed and the
repressurization valve (V15) is opened. The right
tower slowly repressurizes to full line pressure and
is ready to go back on-line.

(2) Right Tower Drying - Left Tower Regenerating

At the start of the drying cycle, both inlet valves
(V1,V2) are open. The left inlet valve (V1) is then
closed to isolate the two towers. The right tower is
now on-line, drying the compressed air. The left
tower will be regenerated, following a similar
sequence as described in Section 4.3.A.(1) for the
right tower.

Connections - An air sample for the transmitter is
taken from the dryer outlet. An isolation valve is
provided in the sample line in case the transmitter
must be removed for service. The flow cell on the
transmitter has a 2 micron filter in the inlet connec-
tion and an orifice fitting in the outlet connection.
The orifice sets the sample flow rate to approxi-
mately 1 scfh at 100 psig.

High-Limit Temperature Controller (TC 4) - The
Controller (see HHC2 on the electrical schematic
supplied separately with dryer) monitors the air
temperature in the piping between the blower and
the heater. If the temperature exceeds the factory
setting of 175ºF during first stage regeneration
(heating), the blower and heater are de-energized
and Alarm (L5 or R5) will be activated.

High Outlet Dew Point Alarm (L8 and R8) - If the
dryer outlet dew point exceeds the alarm set point,
the high outlet dew point alarm for the on-line
tower will be activated. To prevent nuisance
tripping following tower switch-over (see Section
2.0D), the alarm is disabled for the first 57 minutes
of the drying cycle. While the alarm is disabled, the
dryer outlet dew point is displayed on the operator
interface.