Clary SP170-PDA - Manual (Page 8)

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drawing its power from the battery pack. This operation continues until good utility power is
restored, after which, the relays switch back to route the utility power to the PDA module which
powers the cabinet.
With Standby operation, 0.5 seconds (user programmable from 30ms to 2.5sec) after an outage is
detected, standby power is connected to the system and if desired, the Flash Command is
initiated, forcing the cabinet into Flash Mode operation. Depending on the size of the battery
system being used and the loading on the power system, backup power can continue for several
hours. NOTE: If the flash mode operation is not desired, make sure intersection load is not over
the rated output power.
When utility power returns, the UPS module waits 30 seconds to be sure that the utility power has
stabilized. After this built-in safety delay utility power is restored, powering the cabinet. The
battery charger then recharges the batteries in typically 10 to 20 times (depending on the load)
the duration of the outage or battery discharge time (whichever is shorter).
The UPS module can be set to force a break in power of 2.5 seconds after utility power returns.
This is optional (not the default) and is used in intersections when a hard-restart needs to be
applied to various devices when returning from flash.
Continuous Operating Mode (ONLINE):
Continuous operation is used for low power applications such as full LED intersections, power to
the intersection is continuously conditioned and backed up by the UPS. Within the limitation of
the battery capacity, virtually all brownout and power outages are eliminated.
SP1250PD (PLUS) OPTIONAL
The PLUS has an extended load option that will allow up to1400 watts peak load for ten seconds.
This option allows for support of intersections that have not yet replaced the yellow incandescent
traffic lamps.
Additional Notes on Operating Modes:
• The SP170-PDA Series Unit is designed for compatibility with, and complete transparency
to, all traffic signal cabinet functions including police panel operation.
RELAY CONTACTS:
The UPS includes four (4) sets of normally-open (NO) and normally-closed (NC) relay style
contacts. The contacts are intended to connect to the Flash controllers or other devices in the
traffic cabinet. The contacts are actuated at various times as a means of signaling these devices
of important aspects of current operation. These relays can be programmed from the Front Panel
LCD Display. You can set any of the relays to a certain condition listed in Table 11. See section
4.10 for programming instructions. You can access these relays via the Terminal Block (T5) on
the Rear panel of the unit.