Schweitzer Engineering SEL-351P, Quick Start Manual

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Date Code 990430 Breaker/Recloser Monitor, Battery System Monitor, 8-15
Metering, and Load Profile Functions
SEL-351P Manual Técnico
•
% Battery capacity for sleep (0 -100) SLPCAP = ______
•
Turn on the 12 V power (Y,N) ON12V = ______
•
Keep the 12 V power on while asleep (Y,N) 12VSLP = ______
These settings are available via the SET FZ (EZ global settings) or the SET G (global settings)
commands. See the
Settings section in the SEL-351P Quick-Start Installation and User’s
Guide for more information on the EZ global settings.
Battery System Operation
A 24 Vdc battery system powers the SEL-351P and provides trip and close power to the
capacitors when the 120 Vac source is deenergized. The SEL-351P includes a temperature-
compensated, dual rate, 24 V battery charger powered from an external 120 Vac source.
When the 120 Vac source is energized, the SEL-351P built-in battery monitor/charger controls
charging current to the battery system. The SEL-351P monitors the battery charge/discharge
current, battery voltage, and internal control temperature. The SEL-351P calculates the capacity
of the batteries based on these measured values. If the calculated battery capacity is 90% or
higher, the SEL-351P charges the batteries at a low charge rate of 15 mA. If the calculated
battery capacity is less than 90%, the SEL-351P charges the batteries at a high charge rate of 150
mA.
The CHRGG Relay Word bit asserts when the batteries are charging (when the 120 Vac source
is energized). The DISCHG Relay Word bit asserts when the batteries are discharging (when
the 120 Vac source is deenergized and the SEL-351P is operating from battery power). If the
charging current drops below 5 mA, or the discharge current drops below 100 mA, the battery is
considered failed or disconnected. In either case, the
NOBATT Relay Word bit asserts. If the
battery monitor/charger board is OK inside the SEL-351P, the BCBOK Relay Word bit remains
asserted.
The SEL-351P also periodically tests the batteries by subjecting them to a 1-A load for 5
seconds. During the test, the “discharge test in progress” Relay Word bit
DISTST asserts. If the
battery voltage remains above a preset temperature-compensated threshold of 80%, the battery is
OK. If the battery voltage falls below this threshold during the test, the “discharge test failure”
Relay Word bit
DTFAIL asserts, and the “Battery Problem” LED illuminates on the front panel.
DTFAIL remains asserted until the next successful battery load test.
SEL-351P Puts Itself “To Sleep”
If the 120 Vac source is deenergized, the SEL-351P operates off of battery power and continually
calculates remaining battery capacity, as discussed previously. The SEL-351P puts itself to sleep
during an extended outage (it shuts down to conserve battery energy – the front panel goes dark,
too) if either of the following occur:
•
The % Battery capacity for sleep setting (e.g., 20% capacity) is reached
•
Or the temperature-compensated battery voltage falls below 80%
Ten minutes before the SEL-351P puts itself to sleep, the TOSLP Relay Word bit asserts and
remains asserted until the SEL-351P goes to sleep. This bit can be used to trigger a row in the