Page 4
Introduction
The SAR-20 Smart Alternator Regulator
commands maximum safe output from your 12 or
24VDCalternatorwhilemonitoringbatteryvoltage
and temperature. The bulk of the battery charge is
delivered at maximum alternator output allowing
batteryvoltagetoriseuntilthe"absorptionvoltage"
has been reached. The SAR-20 then lowers the
alternator output to maintain a constant battery
voltage at the absorption point. The absorption
voltageismaintainedforaperiodoftimedependent
upon several factors and then the SAR-20 cuts
back the battery voltage to a safe "float" voltage.
TheSAR-20willalsoenableyoutodesulfateyour
battery plates by enabling an "equalization cycle"
(In float mode, press front panel switch for 15
seconds).During equalizationthe SAR-20slowly
raisesbatteryvoltagetoanequalizationlevelwhile
limiting the charge current to about 4-6% of your
battery'samp-hour capacity.This safelydissolves
the sulfates that form on the battery plates during
discharge and extends battery life. The SAR-20
will stay in the equalization stage until the
Programming the Jumpers
Your Smart Alternator Regulator (SAR) is pro-
vided with nine black programming jumpers.
These jumpers are placed on the programming
pins (shown below, Figure 2, and Page 14) as
needed. ThejumperstelltheSARbatteryvoltage,
alternatorsize,batterybankcapacity,batterychem-
istry and if your alternator is "hot" rated.
Ifyourbatteryisawetcelltype,placeajumperon
the "Wet/Gel" location. If your alternator can
deliver maximum output continuously without
burningup,placeajumperonthe"HotRated/No"
location. Remove the jumper on the 12/24V line
ifyouare usingtheSAR-20 witha24V alternator
or keep the jumper in place if using 12V.
Placejumpersasshownonpage14toprogramthe
sizeof youralternator andthe sizeof yourbattery
bank. 12 VDC
Operation 24 VDC
Operation
Page 15
Page 13
SARMAN-O 1999 BV Engineering
http://www.cruzpro.com
Other CruzPro Products
lDepthsounder & Depthsounder /w Water Temperature
lSpeed/Log/w Water Temperature Display
lDC Volts/Amps/Amp-Hour Monitors
lAC Volts/Amps/Frequency/kW Monitor
lLPG/Petrol Gas Detectors/Alarms
lBilge Water Detector/Alarms & Pump Controllers
lWindlass Controller/Chain Counter
lDigital Fuel Gauge/Consumption Calculator
lSmart and Manual Alternator Regulators
lMarine Security System
lRPM/Engine Hours/Elapsed Time Gauge
lDigital Oil Pressure Gauge/Alarm
lDigital Water Temperature Gauge/Alarm
lDigital Amps Gauge
l3 Bank Digital Volts Gauge/Alarm
lDigital Clock/Watch/Race Timers/Alarms
l8 and 16 Amp Light Dimmers
lBattery Voltage Monitors/Alarms
lSolar Panel Charge Controllers
l4 & 8 Channel NMEA Combiners/RS-232 Convertors
lEngine/Exhaust Temperature Monitor/Alarm
lNMEA 0183 Remote Data Repeater/w 4 Input Channels
Full details at http://www.cruzpro.com
SUMMARY & WARNINGS
Indicator LED:
l
1blink per 2 seconds -Bulk deliverystage
l
2 blinks per 2 seconds - Absorption stage
l
3 blinks per 2 seconds - Float stage
l
Continuous blinking - Equalization stage
l
No blinking - Loss of input voltage or loss
ofbatteryvoltagesenseline(automaticshut-
down within 30 seconds typical, one minute
maximum).
To energize an Equalization cycle: When
theSAR20 indicatorLED blinks3 timesper
2 seconds (float mode) you can start an
equalization cycle (see page 4) by holding
down the front panel button for 15 seconds.
Be sure to disconnect anything that can't
handle equalization level voltages (up to
16.5 VDC or 33 VDC). If you connect or
disconnectanyloadsfromthebatterywhile
in equalization mode, the equalization
current will not be correct - don't do it.
