Dwyer DCT1000 - Manual (Page 4)

4-20 mA CONNECTIONS
RECEIVER
USING DCT1000
24V SUPPLY
RECEIVER
SUPPLY
OPTIONAL
CONNECTION
USING EXTERNAL
POWER SUPPLY
4-20 MA
OUTPUT
TB4 4-20 MA SOURCE EXTERNAL INTERNAL ALARM
CONT
ACTS
TB5
NORMALLY OPEN CONTRACTS
MASTER CONTROLLER
MASTER CONTROLLER
INPUT MUST NOT BE
CONNECTED
TO ADDITIONAL
EXPANDER MODULES
SLAVE CHANNEL EXPANDER
HIGH
LIMIT LOW
LIMIT
COM
TB3
COM
ALARM
MODE
MAN
OVR D1
CLN
ALARM
RESETCOM
DAISY CHAIN OUT
DAISY CHAIN IN
DAISY CHAIN OUT
DAISY CHAIN IN
(INTERNALLY CONNECTED)
TB1
L1 L2 SOL
COM
1 2 3 4 5 6 7 8 9 10
(10 CHANNEL SHOWN)
SOLENOIDS
LINE
INPUT
SOLENOIDS
LINE
INPUT
L1 L2 SOL
COM
1 2 3 4 5 6 7 8 9 10
(INTERNALLY CONNECTED)
TB1 (10 CHANNEL SHOWN)
F1
C3Ø4
SUPPLY
ALARM
LOAD
TB2
1.2.2 Manual Override Switch Connection
The manual override function allows the system to be set to the run
mode regardless of other conditions. This mode is enabled when
the manual override terminal and common are connected. It is dis-
abled when they are disconnected. If the controller is to be run in
continuous mode, a jumper wire may be wired across these termi-
nals. When manual override is needed on a periodic basis, wire a
SPST toggle switch between the manual override terminal and the
common terminal.
1.2.3 Down Time Clean Connection
The down time clean operation forces the system into a run cycle
for a programmed length of time between 0 – 255 minutes. The
operation is initiated by connecting the down time clean terminal to
a common terminal. This function is best accomplished through use
of an external normally open switch.
1.2.4 Connecting Multiple Timer Boards
Both master controller boards and slave boards can have up to a
maximum of 22 channels each. The system may be expanded up
to 255 channels using master controller boards and slave boards.
The DCT1000 will automatically detect the total number of channels
involved and make their outputs available. You will note that both
the master controllers and slave boards have a telephone style con-
nector mounted on the upper right hand side of the board. These
connectors are for use in systems requiring slave boards that must
be daisy chained together to provide additional channel capability.
For systems that require the slave boards, the master controller
must not have any connection made to its daisy chain input unless
it is designated as a slave control itself. (For larger systems requir-
ing more than three slave boards, a master controller must be used
as the fourth slave board to satisfy power requirements.) This
sequence would repeat itself until the limit of 255 channels has been
reached. The cables used are not ordinary telephone style cables.
Caution: Do not use telephone jumper cables. These
have a “twist” in the connection and may damage the
controllers. Cables designed for use with the DCT1000
are available from Dwyer Instruments (Model DCAC02-2
ft., DCAC04-4 ft., etc.).
1.2.5 Continuous Cycle Mode
The master controller has several operating modes available for dif-
ferent applications. Starting with the most basic mode, it is capable
of operating in a continuous cleaning cycle. This can be initiated by
either placing a jumper between the high limit input and the com-
mon, or the manual override input to the common connection.
Controlling this cycle are three setup parameters: time off, time on,
and cycle delay. Time on and time off specifically deal with the sole-
noid on time and the time interval between the end of the on pulse
and the start of the next. The cycle delay allows a delay of up to 255
minutes to be programmed between the end of one complete
cleaning cycle and the beginning of the next. This allows additional
options for defining a cleaning profile.
Figure 2
Wiring Connections
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