Call 888.852.2778 for Technical Support 9
Install and Wire Exterior Photocell (Optional)
The LP8 has a specific terminal block for connection to a
Watt Stopper EM-24A2 exterior photocell. This photocell
works in conjunction with the clock’s automation scenarios
to provide automatic exterior lighting control. See the
Users Guide for programming information.
1. Mount the EM-24A2 on the building roof or exterior.
Mount it so the light sensing window faces North.
2. Connect the two black wires and two red wires on the
EM-24A2 to the PCELL terminal block at the top of the
“C8” board on the low voltage side of the LP8 interior.
Using Low Voltage Sensors with LP Panels
When connected as shown in the Low Voltage Wiring section,
the sensor is powered by the panel’s auxiliary power supply. It
controls a relay when connected to a relay input. It controls a group of relays when connected to a GS input.
Control behavior depends on the input to which the sensor is connected.
• Sensor connected to a relay input: sensor controls the relay based on the scheduled state of the relay
Scheduled OPEN: sensor turns relay ON but will not turn it OFF
Scheduled CLOSED: sensor turns relay ON and OFF
• Sensor connected to a GS card input: sensor turns the group of relays ON and OFF regardless of
individual relay schedules.
To remove a sensor from the panel system after it has been commissioned, see Troubleshooting item 7.
Group Switching (GS Card) and Smartwire Procedure (Optional)
The Group Switching card provides eight channels (A-H), which
can be Smartwired to relays in the panel. GS channels are used
to group relays for common control by switches or sensors. Do
not confuse the GS channels with scheduling channels (discussed
in the Users Guide). Group channels created using the GS card
are used with switches or sensors connected to the card’s inputs
as shown in Fig. 3. These groups can be set to exactly or parially
match the scheduling channels as required.
Smartwire Setup
1. On the Group Switching card, press and hold the Group push-
button for several seconds. The red group LED and the LEDs for
relays currently controlled by that input will begin to flash.
2. On each Relay Driver card, select the relays to be controlled.
If a relay was previously Smartwired to the group input selected,
the LED flashes, otherwise the LED is off. Press the associated
Relay Control Button to add/delete that relay to/from the group.
The LED for each relay included in the group flashes.
3. On the Group Switching card, press the Group push-button
again. All LEDs stop flashing and the input switch will now
control the relays selected.
(1) Press Relay
Control Button
on each relay
to be controlled
(2) LED starts flashing
Step 2. RELAY DRIVER CARD
TO RELAY
LED
R B Y W
Step 3. GROUP SWITCHING CARD
(2) LED stops flashing
TO SWITCH
(1) Press Group
Push-button again
Step 1. GROUP SWITCHING CARD
(2) LED starts flashing
TO SWITCH
(1) Press and Hold Group
Push-button
Test Smartwired Relay Group Channels
1. Press the Group Push-button ON/OFF/ON to toggle the group ON/OFF/
ON. The input LED will track the last action.
2. With all relays in the group ON, turn OFF each relay in the group using
the individual Relay Control Buttons on the Relay Driver card. When the
last relay is turned off, the Group LED should also go off.
Group control connectors (8x)
(connect to switch or sensor
contacts, or analog photocells)
Power for
sensors
and
accessories
oup
oup
ABCDEFGH
R
B
Y
WR
B
Y
W
R
B
Y
W
R
B
Y
W
R
B
Y
W
24VDC
24VDC
24VDC
24VDC
YELCOM
24VR
24VAC
WHITE
R
B
Y
W
R
B
Y
W
R
B
Y
W
Install jumper
from YELCOM
to 24VR when
connecting
pilot to group
Ye
(4) #18 AWG
Mount Photocell on exterior or roof of building.
Light sensing window
Point toward North
1/2" thread tting
BLK
BLK
RED
RED
Sliding Window
As it is moved up,
lights turn on
earlier, and turn
off later. Locknut
PCELL
J1
C8
BLK
BLK
RED
RED
C8 Board on
LP8 Interior
Figure 10: Installing the EM-24A2 Exterior
Photocell with the LP8
Group LED Status Indicators
Red: All relays in group ON
Green: Relay group in mixed
state (some ON, some OFF)
Off: All relays in group OFF
Figure12: Smartwire Steps
Figure 11: Group Switching
