The MC28 function provides a sequence for Relay 1 and/
or Relay 2 triggered by Input 1 or ‘WET’ Input. Additionally
Input 2 provides a door position switch input which allows the
delay to run when Input 2 is opened, but not run when closed.
Simply put, this function is an MC25 with a normally opened
door position switch input to determine if the delay should run.
Adjustable parameters include
H1
for activation hold time of
Relay 1,
H2
for activation hold time of Relay 2 and
D1
for delay
between activation of Relay 1 to Relay 2. A maintained input will
freeze both hold timers, thus keeping their relays active until the
input is released, which will allow the hold timers to expire and
deactivate the relays normally.
NOTE
: The delay timer will only fire when Input 2 is opened.
NOTE: The door position switch must have an opened contact
when the door is closed, and a closed contact when it is
not. (Position switch logic is different than 21, 22, 50 and
55.)
A typical application is a security door in which you have a push-
plate to start the sequence to unlock the security device, such as
a Maglock or electric strike and then activate the door controller
and an additional door position switch. For this scenario the
push-plate would be wired to Input 1, the position switch would
be wired to Input 2, the security device would be wired to Relay
1 and the door controller would be wired to Relay 2. An example
wiring diagram for this scenario is shown.
NOTE: While the ‘WET’ Input is not involved in our typical
application, it will still function as Input 1 does if used.
MC28 SETUP
1. Wire the Br3 accordingly.
2. Select the MC28 as the function according to the steps outlined in Section 5 – Selecting the Function.
• Press and hold both push buttons (INCR & PARAM) for three (3) seconds to activate the display.
• Press the INCR button to toggle through each function and select
28
.
3. Set the MC28 parameters according to the steps outlined in Section 5 – Selecting the Function.
• Press PARAM button to cycle through and set the parameters.
• Press the INCR button to increment the parameter’s value.
Parameters for the MC28 function are shown in the chart. Set the parameters as needed for the application, and wait for the display to
become inactive to save the configuration.
PARAMETER
(PARAM Button)
DESCRIPTION
POSSIBLE VALUES
(INCR Button)
H1
Relay 1 hold time
‘
00
’ through ‘
60
’ - Relay 1 hold time will not begin counting down until the release of Input 1 or
‘WET’ Input.
H2
Relay 2 hold time
‘
00
’ through ‘
60
’ - Relay 2 hold time will not begin counting down until the delay between
Relay 1 and Relay 2 expires.
D1
Delay between
Relay 1 and Relay 2
‘
00
’, ‘_
1
’ (1/4), ‘_
2
’ (1/2), ‘_
3
’ (3/4), ‘
01
’ through ‘
60
’ seconds. The delay time will begin
counting down with the activation of the sequence.
4. Once programming is complete, test the Br3. Trigger the sequence via Input 1 or ‘WET’ Input. Ensure that the sequence runs and the
relays activate and the timers are as programmed. The display will show
R1
when Relay 1 is energized,
R2
when Relay 2 is energized and
R=
when both Relay 1 and Relay 2 are energized at the same time. Ensure that the delay between Relay 1 and Relay 2 runs when the
sequence starts from the door closed position. Now, re-run the sequence; however this time before the door reaches the closed position,
reactivate the door and ensure that the door reactivates immediately as the delay between timer,
D1
does NOT run.
5. Upon completion of the above steps, walk test the door to ensure all functions, timers, sensors, etc. are working as intended and that the
system is in compliance with all applicable standards (i.e. ANSI A156.10, A156.19).
6F Function
28
- 2 Relay Sequence w/Position Input (MC28)
75.5501.02 EN 20091102 (75.5500)
Page 8 of 15
G
N
D
IN
-1
G
N
D
IN
-2
G
N
D
IN
-3
G
N
D
IN
-4
1
2
3
4
WET
WET
WET
N
C
N
O
C
O
M
N
C
N
O
C
O
M
12
-2
4V
AC
/D
C
RELAYS
1
2
POWER
RELAY 1
IN
C
R
.
PARAM
SETUP
D
C
AC
D
R
Y
W
ET
INPUTS
2 8
N
C
N
O
C
O
M
3
Br
3
CAUTION: RELAY 1 WET
OUTPUT OPTION
IS ACTIVE FOR
ALL FUNCTIONS.
12 to 24
VAC/VDC
+/- 10%
To Activation Circuit
of Door Control.
Pushplate or other
Dry Contact Device.
‘WET’
12 to 24
VAC/VDC
+/- 10%
INPUT
+ -
Typically Connected to Lock Device. When DC ‘WET’
Output is Selected for Relay 1, COM Terminal is Positive (+).
Input 2 is for the Door Position Switch.
Switch is open when door is closed.
