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10
Example 1
Four Smart Pad
2
’s (with Status), five 780-80’s (with Status), two PA640’s and one 599 Pulsed Switching
Module are used. Add up the currents: (4 x 90 mA) + (5 x 30 mA) + (2 x 11 mA) + (1 x 11 mA) = 543 mA
total. This is well within the
1.8 A
(1800 mA) limit. Therefore, no external power supply is needed.
Example 2
24 Smart Pad
2
’s (4 per zone, with Status), twelve 780-80’s (2 per zone, with Status), two PA640’s and one
599 Pulsed Switching Module are used. Add up the currents: (24 x 90 mA) + (12 x 30 mA) + (2 x 11 mA)
+ (1 x 11 mA) = 2553 mA total current. This exceeds the
1.8 A
limit by 753 mA. Therefore, a 782-00 external
power supply is needed to power the extra Smart Pad
2
’s and IR receivers that cause the
1.8 A
limit to be
exceeded. In this case, you would have to power seven Smart Pad
2
’s and five 780-80 IR Receivers
externally (780 mA) to ease the load sufficiently.
Fig. 7 Using a CB18 to provide a +12V DC rail (if needed) to externally power extra keypads and IR receivers to prevent overload
of the internal power supply of the ZPR68-10.
ZONE CONTROL - IR INPUTS
+12V
GND
STATUS
IR IN
9
8
6
7
4
5
2
3
1
ZPR68-10
Zone Control - IR Inputs section
120 V AC
(Unswitched)
782-00
Power Supply
Smart Pad
2 or 3
(Four shown)
780-80
"J" Box
IR Receivers
(Five shown)
V
IR
ST
G
V
IR
ST
G
V
IR
ST
G
V
IR
ST
G
V
IR
ST
G
+12V
(white
striped
side)
GND
GND
+12V
V
IR
ST
G
V
IR
ST
G
V
IR
ST
G
V
IR
ST
G
V = +12V
IR = IR Signal
ST = Status
G = GND
CB18
"The Strip-IR"
Connecting Block
Fig. 7 illustrates how you can do this by using a CB18 "Strip-IR" Parallel Connecting Block to provide a
separate +12V DC rail. This powers the additional IR receivers and keypads independent of the +12V of
the ZPR68-10.
NOTE: The 782-00 Power Supply has a capacity of 1000 mA. If you have a system that is so extensive
that the total current exceeds the 1.8 A limit of the ZPR68-10 by more than 1000 mA, use two 782-00's
connected so that two se12V DC rails are created. Connect two groups of the extra devices so
that the total excess load is shared equally between the two 782-00's.
CAUTION: To prevent current "hogging" and power supply shutdown, never connect a 782-00 in parallel
with the +12V terminal of the ZPR68-10 or in parallel with another 782-00!
ZPR68-10