Installation Instructions

PN# 500-10300
Page 2 Rev. D, 04/11
3.2 DC OUTPUT
The maximum DC output of the power supply is expressed by the final figure in the part
number. The BPS-24-3 can supply up to 3 amps; the BPS-12-6, up to 6 amps etc. However,
these power supplies are adjustable and the voltage level set affects the current output capacity.
When used with batteries, the power supplies must be set at 12.5% over voltage (13.5 V for
12 volt supplies and 27 V for 24 volt supplies). This is the factory setting and if the voltage is
to be changed, use the potentiometer marked "V Adj" on the power supply module. The current
rating takes into account the possibility of the supplies operating at 12.5% over voltage.
Therefore any supply which is operated at its nominal voltage (12 or 24 v) can supply about
20% more than its rated current. Despite this, we strongly recommend that supplies be
operated substantially below their maximum output capability. Operating power supplies at
their maximum greatly increases the possibility of heat induced failure. "Margin for error" is lost
and this is inappropriate for a security system. Power supplies should be run at no more
than two thirds of their maximum capacity for optimum reliability
3.3 EMERGENCY RELEASE TERMINALS
If the power module is operating or if batteries are operating, the LED will illuminate. +V (12 or
24VDC depending on the model power supply) will then be on terminal F1. Connection must
then be made between terminals F1 and F2 before +V is routed to the "P" terminals. Terminals
F1 and F2 therefore constitute an emergency release point. If desired, for instance, NC
contacts controlled by the user's fire alarm system can be connected across terminals F1 and F2
such that the connection between these terminals will be broken in the event of a fire. UL
listed auxiliary latching normally closed contacts from the fire alarm system should be
used. "Trouble" contacts must not be used. This will automatically release all the devices being
driven by the unit. If the emergency release terminals are not to be used in this way, a jumper
should be placed between them so that the board's output terminals will function. Make sure
that the switching capability of any switch or relay contacts placed across F1 and F2
can handle the full output load of the power supply.
Terminal FA is a free parking terminal used only with Securitron’s Power Supply Monitor.
The PSM interconnects with the power supply and monitors the continued correct behavior of the
supply including voltage level and whether the batteries are functioning. The PSM signals any
problem including whenever the battery pack takes over the load. If you are using the PSM,
wiring with the FA terminal is shown in the manual.
3.4 OUTPUT TERMINALS
The CCS board has three types of output terminals. “P” terminals are on individual circuit
breakers and carry +12 or +24 volts on them (when the emergency release terminals are
closed). The “H” terminal carries the full +V output of the supply on a single terminal (when
F1 and F2 are closed). Use the “H” terminal for applications where the device being powered
requires more than 2 Amps of current. The Polyswitch circuit breakers cannot reliably supply
more than 2 Amps of current without tripping and you should never wire multiple “P”
terminals in parallel to supply increased current. This bypasses the safety role of the
Polyswitch breakers and also does not work very well. When two “P” terminals are wired in
parallel, current carrying capacity is not doubled. The current conducted through the two
terminals will not be identical so one switch will break first and then the second will immediately
trip. When “P” terminals are correctly used as isolated outputs, each is inherently current
limited to Class 2 standards. Always use the “H” terminal for applications requiring high
current. Finally, the “R” terminals are all for 0 volt DC negative return and are in common.
3.5 FUSING AND CIRCUIT POLYSWITCHES
An AC fuse, DC fuse and four or eight Polyswitches are present on the board. The AC fuse is
on the hot 120 VAC input and protects against an internal short in the power supply transformer.
A short in the DC load will not blow the AC fuse. The DC fuse protects the full DC output of the
supply prior to it being divided through the Polyswitches to the individual “P” outputs. The
Polyswitch is a special type of automatic circuit breaker. If one of the Polyswitches receives an
overload, it will rapidly cut the current down to a small leakage current (about 100 mA) which
will allow the rest of the installation to continue to operate. Note that each “P” output
includes a slide switch and LED. The slide switch can cut DC power to its respective output and
the LED monitors when the output is powered. In the event of one of the Polyswitches tripping,
the associated LED will go out. If all the LED’s go out, one of the fuses has tripped or the power