DEZ
S
ERIES
1000
I
NSTALLATION
,
O
PERATION AND
M
AINTENANCE
M
ANUAL
10
air will enter one side of the unit cool and will leave
the other side very warm and moist.
3.3 Reactivation Heater Controller
This unit may be equipped with a solid-state
temperature controller or with a microprocessor-
based temperature controller. Generally, these
control devices are used to modulate the on-board
reactivation heater to maintain the reactivation
discharge air temperature setpoint. The controller
is shipped from the factory pre-programmed. The
source manufacturer’s instructions for the
controller are provided under separate cover.
Refer to the source manufacturer’s manual for
detailed information on operating the controller
and adjusting control parameters.
3.4 Capacity Control
The DEZ Series 1000 can be configured with one
of two controllers: A Watlow controller, which
comes standard with the unit, or optionally, the
STULZ E
2
microprocessor controller. The control
methods (described in the following sections) that
are available to the unit depend on which
controller is used.
The Watlow controller provides two basic control
methods 1) D-Stat and 2) D-Stat II. The E2
controller supports both of these methods, plus
H-Trac, Dew-Trac, and C-Trol II methods.
Refer to your order sheet or DIN Sheet for the
control method used in your unit.
3.4.1 D-Stat
What it Does:
This control method cycles the dehumidifier
on and off to maintain the relative humidity
setting.
Requires:
A wall-mounted humidistat or dry contact to
enable remote start/stop.
How it Works:
The dehumidifier responds to a control signal
from a humidistat (provided as an option) or a
customer-supplied dry contact control signal
which cycles the unit on and off to maintain
the relative humidity setting. See section
3.5.1, Mode Selector Switch for the correct
mode setting to enable humidistat control.
3.4.1.1 D-Stat II
This control method function is similar to D-Stat,
except the process blower runs continually. The
reactivation heater and blower cycle on and off in
response to a humidistat (provided as an option)
or a customer-supplied dry contact control signal.
3.4.2 H-Trac
What it Does:
This control automatically regulates the
reactivation heater to provide constant
process discharge or space relative humidity.
Requires:
A factory or space-mounted RH
sensor/transmitter and adjustable setpoint
microprocessor controller.
How it Works:
The controller sends a signal to the on-board
reactivation heater modulation control system
to maintain the relative humidity setpoint. The
dehumidifier runs continuously and
continually adjusts capacity in response to
load changes. In the AUTO mode, the
dehumidifier responds to a customer-supplied
start/stop signal.
3.4.3 Dew-Trac
What it Does:
This control method regulates the reactivation
heater to provide constant process discharge
or space dewpoint temperature.
Requires:
A factory or space-mounted dewpoint
transmitter and adjustable setpoint
microprocessor controller.
How it Works:
The controller determines the amount of
reactivation energy required to maintain the
dewpoint setpoint and develops an
appropriate control output. The dehumidifier
runs continuously and the controller
continually adjusts reactivation heat in
response to load changes. In Remote mode
the dehumidifier responds to a customer-
supplied start/stop signal.
3.4.4 C-Trol
II
What it Does:
This control method regulates reactivation
heat, to prevent condensation from forming on
cold surfaces, by maintaining the ambient
dewpoint temperature below the temperature
of the cold surface.
