Installation Instructions (37KB)
M1DBH Data Bus Hub Installation
The M1DBH is pre-assembled on a 3" structured wiring plate (ELK-SWP3), which mounts inside any ELK
Structured Wiring Enclosure. Four (4) black push-pin style fasteners mount the plate to the enclosure. If desired,
the board may also be removed from the plate and mounted with double faced tape.
1. Connect the +VKP, Data A, Data B, and Neg data bus terminals from the M1 board to the top four (4) input
terminals on the M1DBH board using a (4) conductor cable.
2. Pull Category 5 Cable (CAT5) from each data bus device to the control.
3. Terminate each CAT5 data bus cable with an RJ45 plug using the appropriate crimping tool. Use the 568A
wiring standard (see wire color code below). Note: RJ45 plugs are not included with the M1DBH due to the
great variety of brands and terminating tools which are subject to dealer preference.
3. Following the color codes used in step 2 and the wring diagram below, connect the CAT5 cable at each device.
The Pos & Neg wires connect singularly to the Pos & Neg terminations (flying lead wires or terminals) of the
keypad, zone expander, etc. However the data A & B lines are connected to the device along with a "return" wire
so that the data returns back to the M1DBH, which is then used to feed the next device. Effectively, this puts the
data lines in a series circuit so that the control communcates with each device in a progression or "daisy chain"
fashion. The very end of this daisy chain (which will be the two return wires from the last data bus device)
requires a terminating resistor (see step 5). This is very important due to the high speed of the M1's RS-485
data bus communications.
4. Place each data bus cable into it's own RJ45 jack on the M1DBH board starting with J1. If there are more than 9
data bus cables, add a second M1DBH and connect the short CAT5 jumper (included) from J9 on the previous
M1DBH board to J1 on the next M1DBH board. This leaves 8 jacks on the first M1DBH and 8 on the second or
a total of 16 potential jacks (ports). Additional M1DBH boards may be connected for more cables.
5. Place the EOL resistor terminating plug (included) into the first unused jack. This plug places a 120 Ohm
resistor across the A & B data return lines coming from the last wired device, effectively terminating the bus.
The ELK-M1DBH Data Bus Hub is the ideal way to connect multiple home run cables to the M1. It accepts CAT5
or CAT6 cable with RJ45 plugs on the ends. The M1DBH does the work of series connecting DATA lines A & B
and provides a clean, organized method for managing the data bus wires. Data bus termination is done at the
hub with an RJ45 Terminating Plug (included) placed into the first unused jack.
Maximum "TOTAL" Length of the M1 RS-485 Data Bus should NOT exceed 4000 feet.
When calculating the total length, figure the length of each home run to the M1DBH times 2 (x 2)
since the data lines run out and back. Maximum number of data bus devices varies by control.)
WARNING! The RS485 Data Bus must NEVER
have more that two (2) terminating resistors
header/jumpers installed. Reliability and
response will be negatively affect
ed!
Keypad
Keypad
Keypad
8 - Brn/Wht
7 - Wht/Brn
6 - Org/Wht
5 - Wht/Blue
4 - Blue/Wht
3 - Wht/Org
2 - Grn/Wht
1 - Wht/Grn
Keypad
RED +12V
BLACK (-)
GREEN (A)
WHITE (B)
BLUE
BROWN
Pin1
RJ45 Plug
A
1
G
r
n
/
W
h
t
A
O
r
g
/
W
h
t
-
W
h
t
/
B
r
n
+
B
r
n
/
W
h
t
B
W
h
t/
O
r
g
B1
W
h
t
/
G
r
n
ELK-M1DBH Data Bus Hub
Mount M1DBH inside control.
Connect it to the M1 Data Bus
terminals using a 4 conductor cable.
CAT5 or
CAT6 Cable
Color Code and Connections of CAT5 or CAT6 Data Bus Cable from Keypad to Data Bus Hub
Pin1
J2
J4 J6 J8
J1 J3 J5 J7 J9
Insert RJ45 Terminating Plug
into first unused jack and
terminate the control at JP3.
DO NOT TERMINATE AT ANY
OF THE DEVICES
!
CAT5 Cables
Optional
Output
Opt.
Zone
Input
Front view
Diagram for Daisy Chain Connection of Data Bus Devices Using ELK-M1DBH And CAT5 Cables.
NEG -
DATA B
+12V
DATA BUS
+VKP
DATA B
DATA A
NEG
EGND
J1J2
JP3 Teminating Jumper
(Located beneath cover)
RS-485 DATA BUS
DATA A
BLACK
RED
GREEN
WHITE
Spare
Spare
M1 Control Board
NOTE: The spare pair (Wht/Blu, Blu/Wht) can be
used to double up power or for other purposes.