Push-Button - Progress Solar/Wind SLT 700 Series Operator's Manual

If the battery bank discharges below 12.30 Volts (24.60 Volts @ 24 V, 49.20 Volts @ 48 V) the previ-
ous night, Float charging stage will be cancelled for the next charge cycle. Figure 4-5 above illus-
trates this concept. At 0:00 hrs (dawn), battery voltage is below the Float Cancel threshold voltage.
The diagram shows where Float stage would have occurred if Float was not cancelled.
Equalize Time-out
Bulk Equalize
Equalize V
Absorp. V
Equalize timeout
1:00 2:00
Figure 4-6. Equalize timeout charging profile
The charging profile in figure 4-6 shows an Equalize Timeout event. The timeout timer begins as soon
as battery voltage exceeds the Absorption voltage setpoint. If there is insufficient charging current or
system loads are too large, the battery voltage may not reach the Equalize setpoint. Equalize Timeout
is a safety feature that prevents high battery voltage for extended periods of time which may damage
the battery.
Temperature Compensation
All charging settings are based on 25°C (77°F). If the battery temperature varies by 5°C, the charg-
ing setting will change by 0.15 Volts for a 12 Volt battery. This is a substantial change in the charg-
ing of the battery, and the use of the Remote Temperature Sensor (RTS) is recommended to adjust
charging to the actual battery temperature.
The need for temperature compensation depends on the temperature variations, battery type, how
the system is used, and other factors. If the battery appears to be gasing too much or not charging
enough, the RTS can be added at any time after the system has been installed. See Section 2.3 -
Step 4 for installation instructions.
Battery Sense
Voltage drops are unavoidable in power cables that carry current, including the TriStar MPPT 150V
battery cables. If Battery Sense wires are not used, the controller must use the voltage reading at the
battery power terminals for regulation. Due to voltage drops in the battery cables, the battery power
connection voltage will be higher than the actual battery bank voltage while charging the battery.
42
Float
time (hrs)
3:00 4:00 5:00 6:00
Operation
Two sense wires, sized from 1.0 to 0.25 mm
Because these wires carry no current, the voltage at the TriStar will be identical to the battery voltage.
A 2-position terminal is used for the battery sense connection. Generally accepted wiring practice is to
limit voltage drops between the charger and the battery to 2%.
Even properly sized wiring with 2% drop can result in a 0.29 Volt drop for 14.4V charging (or 1.15
Volt for a 48 Volt nominal system). Voltage drops will cause some undercharging of the battery. The
controller will begin Absorption or limit equalization at a lower battery voltage because the controller
measures a higher voltage at the controller's terminals than is the actual battery voltage. For
example, if the controller is programmed to start Absorption at 14.4V, when the controller "sees"
14.4V at its battery terminals, the true battery voltage would only be 14.1V if there is a 0.3V drop
between the controller and battery.
Note that the battery sense wires will not power the controller, and the sense wires will not compen-
sate for losses in the power wires between the controller and the battery. The battery sense wires are
used to improve the accuracy of the battery charging.
See Section 3.2 - Step 7 for instructions on how to connect the battery sense wires.

4.3 Push-button

The following functions can be enabled with the push-button (located on the front cover):
PUSH
• Reset from an error or fault.
• Reset the battery service indication if this has been activated in custom settings. A new
service period will be started, and the flashing LEDs will stop blinking. If the battery ser-
vice is performed before the LEDs begin blinking, the push-button must be pushed at the
time when the LEDs are blinking to reset the service interval and stop the blinking.
PUSH AND HOLD 5 SECONDS
• Request battery equalization manually. The TriStar MPPT 150V will begin equaliza-
tion in either the manual or automatic equalization mode. Equalization will begin when
there is sufficient solar power to charge the battery up to the equalization voltage. The
LEDs will blink the sequence defined in table 4-3 below to confirm that an equalize has
been requested. The equalization request will automatically stop per the battery type
selected (see Section 4.4). Equalization will only occur if the selected battery type has an
equalization stage.
• Stop an equalization that is in progress. This will be effective in either the manual or
automatic mode. The equalization will be terminated. The LEDs will blink to confirm the
equalize has been cancelled as shown in table 4-3 below.
Push-button Action
Manual Equalization Started Green / Yellow / Red - Green / Yellow / Red - Green - Green
Stop Equalization Green / Yellow / Red - Green / Yellow / Red - Red - Red
Table 4-3. Manual equalization LED indications
TriStar MPPT Operator's Manual
(16 to 24 AWG), can be used for battery voltage sense.
2
SOC LED Indication
1
43