3. Installation
3.1. Location of the inverter
 | To ensure a trouble free operation of the inverter, it must be used in locations that meet the following requirements: a) Avoid any contact with water. Do not expose the inverter to rain or moisture. b) Do not place the unit in direct sunlight. Ambient air temperature should be between -20°C and 40°C (humidity < 95% non-condensing). c) Do not obstruct the airflow around the inverter. Leave at least 30 centimeters clearance above and below the inverter, and preferably installed upright and vertical When the unit is running too hot, it will shut down. When it has reached a safe temperature level the unit will automatically restart again. |
 | This product contains potentially dangerous voltages. It should only be installed under the supervision of a suitable qualified installer with the appropriate training, and subject to local requirements. Please contact Victron Energy for further information or necessary training. |
| Excessively high ambient temperature will result in the following: · Reduced service life. · Reduced charging current. · Reduced peak capacity, or shutdown of the inverter. Never position the appliance directly above lead-acid batteries. The unit is suitable for wall mounting. For mounting purposes, a hook and two holes are provided at the back of the casing. The device must be fitted vertically for optimal cooling. |
| For safety purposes, this product should be installed in a heat-resistant environment. You should prevent the presence of e.g. chemicals, synthetic components, curtains or other textiles, etc., in the immediate vicinity. |
Try and keep the distance between the product and the battery to a minimum in order to minimise cable voltage losses
3.2. MPPT grounding, detection of PV array insulation faults & Earth fault alarm notification
The RS will test for sufficient resistive isolation between PV+ and GND, and PV- and GND.
In the event of a resistance below the threshold (indicating an earth fault), the unit will stop charging and display the error.
If an audible alarm and/or email notification of this fault is required, then you must also connect a GX device (such as the Cerbo GX). Email notifications require an internet connection to the GX device and a VRM account to be configured.
The positive and negative conductors of the PV array must be isolated from ground.
Ground the frame of the PV array to local requirements. The ground lug on the chassis should be connected to the common earth.
The conductor from the ground lug on the chassis of the unit to earth should have at least the cross-section of the conductors used for the PV array.
When a PV resistance isolation fault is indicated, do not touch any metal parts and immediately contact a suitably qualified technician to inspect the system for faults.
The battery terminals are galvanically isolated from the PV array. This ensures that PV array voltages cannot leak to the battery side of the system in a fault condition.
3.3. Battery and battery lead requirements
In order to utilize the full capacity of the product, batteries with sufficient capacity and battery cables with sufficient cross section should be used. The use of undersized batteries or battery cables will lead to:
Reduction in system efficiency.
Unwanted system alarms or shutdowns.
Permanent damage to system.
See table for MINIMUM battery and cable requirements.
Model | ||
|---|---|---|
Battery capacity Lead-acid | 200 Ah | |
Battery capacity Lithium | 50 Ah | |
Recommended DC fuse | 125 A - 150 A | |
Minimum cross section (mm2) per + and - connection terminal | 0 - 2 m | 35 mm 2 |
2 - 5 m | 70 mm 2 |
Warning
Consult battery manufacture recommendations to ensure the batteries can take the total charge current of the system. Decision on battery sizing should be made in consultation with your system designer.
| Use a torque wrench with insulated box spanner in order to avoid shorting the battery. Maximum torque: 14 Nm Avoid shorting the battery cables. |
Undo the two screws at the bottom of the enclosure and remove the service panel.
Connect the battery cables.
Tighten the nuts well for minimal contact resistance.
3.4. Solar array configuration
The Inverter RS Solar single tracker model contains multiple PV input connectors. However these are internally connected to one single Maximum Power Point Tracker. It is strongly recommended that the connected strings are made with the same number and type of panels.
The maximum operational input current for each tracker is 18 A.
MPPT PV inputs are protected against reverse polarity, to a maximum short circuit current of 20 A for each tracker.
Connecting PV arrays with a higher short circuit current is possible, up to an absolute maximum of 30A, as long as connected with correct polarity. This outside of specification potential allows for system designers to connect larger arrays, and can be useful to understand in case a certain panel configuration results in a short circuit current just slightly above the maximum of the reverse polarity protection circuit.
Warning
BEWARE that the product warranty will be void if a PV array with a short circuit current larger than 20 A array is connected in reverse polarity.
When the MPPT switches to float stage it reduces battery charge current by increasing the PV Power Point voltage.
The maximum open circuit voltage of the PV array must be less than 8 times the minimum battery voltage when at float.
For example, where a battery has a float voltage of 54.0 volts, the maximum open circuit voltage of the connected array cannot exceed 432 volts.
Where the array voltage exceeds this parameter the system will give a "Over-charge Protection" error and shut down.
To correct this, either increase the battery float voltage, or reduce PV voltage by removing PV panels from the string to bring the voltage back within specification.
3.5. Cable connection sequence
First: Confirm correct battery polarity, connect the battery.
Second: if required, connect the remote on-off, and programmable relay, and communications cables
Third: Confirm correct PV polarity, and then connect the solar array (if incorrectly connected with reverse polarity, the PV voltage will drop, the controller will heat up but will not charge the the battery).
3.6. Connection to the load
Never connect the output of the inverter to another AC supply, such as a household AC wall outlet or AC wave forming petrol generator. Wave synchronising PV solar inverters can be connected to the AC output, see section on Frequency Shift Function for more information.
| The Inverter RS is a safety class I product (supplied with a ground terminal for safety purposes). Its AC output terminals and/or grounding point on the outside of the product must be provided with an uninterruptible grounding point for safety purposes. The Inverter RS is provided with a ground relay that automatically connects the Neutral output to the chassis. This ensures the correct operation of the internal earth leakage switch and an earth leakage circuit breaker that is connected to the output. ─ In a fixed installation, an uninterruptable grounding can be secured by means of the grounding wire of the AC input. Otherwise the casing must be grounded. ─ In a mobile installation (for example, with a shore current plug), interrupting the shore connection will simultaneously disconnect the grounding connection. In that case, the casing must be connected to the chassis (of the vehicle) or to the hull or grounding plate (of the boat). Torque: 2 Nm |
3.7. VE.Direct
This can be used to connect a PC/laptop to configure the inverter with a VE.Direct to USB accessory. Can also be used to connect a Victron GlobalLink 520 to allow for remote data monitoring.
Note the VE.Direct port on the Inverter RS cannot be used to connect to a GX device, and the VE.Can connection must be used instead.
3.8. VE.Can
Used to connect to a GX Device, and/or daily-chain communications to other VE.Can compatible products such as the VE.Can MPPT range.
3.9. Bluetooth
Used to connect to the device via VictronConnect for configuration.
3.10. User I/O
3.10.1. Remote on/off connector
The remote on/off connector has two terminals, the “Remote L” and the “Remote H” terminal.
The Inverter RS ships with the remote on/off connector terminals connected to each other via a wire link.
Note that for the remote connector to be operational, the main on/off switch on the Inverter RS needs to be switched to “on”
The remote on/off connector has two different operational modes:
On/off mode (default):
The default function of the remote on/off connector is to remotely switch the unit on or off.
The unit will switch on if “Remote L” and the “Remote H” are connected to each other (via a remote switch, relay or the wire link).
The unit will switch off if “Remote L” and the “Remote H” are not connected to each other and are free floating.
The unit will switch on if “Remote H” is connected to battery positive (Vcc).
The unit will switch on if “Remote L” is connected to battery negative (GND).
2-wire BMS mode:
This feature can be enabled via VictronConnect. Go to “battery settings” and then to “Remote mode”. (see attached image)
Set the remote mode from “on/off” to “2-wire BMS”.
In this mode, the “load”, “load disconnect” or “allowed to discharge” signal and the “charger”, “charger disconnect” or “allowed to charge” signals from a Victron lithium battery BMS are used to control the unit. They respectively turn the inverter off in case discharge is not allowed, and turn the solar charger off if charging is not allowed by the battery.
Connect the BMS “load”, “load disconnect” or “allowed to discharge” terminal to the Inverter RS Smart “Remote H” terminal.
Connect the BMS “charger”, “charge disconnect” or “allowed to charge” to the unit Inverter RS Smart “Remote L” terminal.
3.10.2. Programmable relay
Programmable relay which can be set for general alarm, DC under voltage or genset start/stop function. DC rating: 4A up to 35VDC and 1A up to 70VDC
3.10.3. Voltage sense
For compensating possible cable losses during charging, two sense wires can be connected directly to the battery or to the positive and negative distribution points. Use wire with a cross-section of 0,75mm².
During battery charging, the charger will compensate the voltage drop over the DC cables up to a maximum of 1 Volt (i.e. 1V over the positive connection and 1V over the negative connection). If the voltage drop threatens to become larger than 1V, the charging current is limited in such a way that the voltage drop remains limited to 1V.
3.10.4. Temperature sensor
For temperature-compensated charging, the temperature sensor (supplied with the unit) can be connected. The sensor is isolated and must be fitted to the negative terminal of the battery. The temperature sensor can also be used for low temperature cut-off when charging lithium batteries (configured in VictronConnect).
3.10.5. Programmable analog/digital input ports
The product is equipped with 2 analog/digital input ports, they are labelled AUX_IN1+ and AUX_IN2+ on the removable User I/O terminal block.
The digital inputs are 0-5v, and when a input is pulled to 0v it is registered as 'closed'
These ports can be configured in VictronConnect.
Unused: the aux input has no function.
Safety switch: the device is on when the aux input is active.
You can assign different functions to each aux input. In case the same function is assigned to both aux inputs then they will be treated as an AND function, so both will need to active for the device to recognise the input.
3.10.6. User I/O terminal diagram
User I/O Connector is located on bottom left side of connection area, diagram shows 3 perspectives. Left Side - Top - Right Side
3.10.7. User I/O functions
Number | Connection | Description |
|---|---|---|
1 | Relay_NO | Programmable relay Normally Open connection |
2 | AUX_IN - | Common negative for programmable auxiliary inputs |
3 | AUX_IN1+ | Programmable auxiliary input 1 positive connection |
4 | AUX_IN2+ | Programmable auxiliary input 2 positive connection |
5 | REMOTE_L | Remote on/off connector Low |
6 | REMOTE_H | Remote on/off connector High |
7 | RELAY_NC | Programmable relay Normally Closed connection |
8 | RELAY_COM | Programmable relay common negative |
9 | TSENSE - | Temperature Sensor negative |
10 | TSENSE + | Temperature Sensor positive |
11 | VSENSE - | Voltage Sensor negative |
12 | VSENSE + | Voltage Sensor positive |
3.11. Programming with VictronConnect
This guide will help you with the specific elements of VictronConnect that relate to the MPPT Solar Charge Controller.
More general information about the VictonConnect App - how to install it; how to pair it with your device; and how to update firmware, for example - can be found by referring to the overall VictronConnect manual. A list of all VictronConnect compatible devices can be viewed here.
Note: These instructions can apply to different products and configurations, where battery voltage is referred to in these instructions, a 12V battery is used as a reference point. Please multiply the given values by 4 to arrive at settings for an installation configured for the 48V battery system.
3.11.1. Settings
 |
The settings page is accessed by clicking on the Cog icon at the top right of the Home page. The settings page provides access to view or change the settings of the Battery; Load; Streetlight; and Port functions. From this page you can also view Product information such as the Firmware versions installed on the MPPT Solar Charger.
3.11.2. Battery settings
 |
Battery voltage
The RS is fixed to 48V, and is only available for 48V systems.
Max charge current
Allows the user to set a lower maximum charge current.
Charger enabled
Toggling this setting turns the Solar Charger off. The batteries will not be charged. This setting is intended only for use when carrying-out work on the installation.
Charger settings - Battery preset
Battery preset allows you to select the battery type; accept factory defaults; or enter your own preset values to be used for the battery charge algorithm. The Absorption voltage, Absorption time, Float voltage, Equalisation voltage and Temperature compensation settings are all configured to a preset value - but can be user-defined.
User-defined presets will be stored in the preset library - in this way installers will not have to define all the values each time they are configuring a new installation.
By selecting Edit Presets, or on the Settings screen (with expert mode on or not), custom parameters can be set as follows:
Absorption voltage
Set the absorption voltage.
Adaptive absorption time
Select with adaptive absorption time or fixed absorption time will be used. Both are better explained below:
Fixed absorption time: The same length of absorption is applied every day (when there is enough solar power) by using the maximum absorption time setting. Be aware that this option can result in overcharging your batteries, especially for lead batteries and system with shallow daily discharges. See your battery manufacturer for recommended settings. Note: make sure to disable the tail current setting to make the same absorption time every day. The tail current could end absorption time sooner if the battery current is below the threshold. See more information on the tail current setting section below.
Adaptive absorption time: The charge algorithm can use an adaptive absorption time: it automatically adapts to the state of charge in the morning. The maximum duration of the absorption period for the day is determined by the battery voltage as measured just before the solar charger begins operation each morning (12 V battery values used - Multiply Battery voltage by 4 for 48V ):
Battery voltage Vb (@start-up) | Multiplier | Maximum absorption times |
|---|---|---|
Vb < 11.9 V | x 1 | 06:00 hours |
> 11.9 V Vb < 12.2 V | x 2/3 | 04:00 hours |
> 12.2 V Vb < 12.6 V | x 1/3 | 02:00 hours |
Vb > 12.6 V | x 2/6 | 01:00 hours |
The multiplier is applied to the maximum absorption time setting and this results in the maximum duration of the absorption period used by the charger. The maximum absorption times shown in the last column of the table are based on the default maximum absorption time setting of 6 hours.
Maximum absorption time (hh:mm)
Set the absorption time limit. Only available when using a custom charge profile.
Enter the time value in the notation hh:mm, where hours are between 0 and 12; and minutes are between 0 and 59.
Float voltage
Set the float voltage.
Re-bulk voltage offset
Set the voltage offset that will be used over the float voltage setting that will determine the threshold that the charge cycle will restart.
E.g.: For a Re-bulk voltage offset off 0.1V and a float voltage setting of 13.8 V, the voltage threshold that will be use to restart the charge cycle will be 13.7 V. In other words, if the battery voltage drops below 13.7 V for one minute, the charge cycle will restart.
Equalization voltage
Set the equalization voltage.
Equalization current percentage
Set the percentage of the Max charge current setting that will be used when equalisation is performed.
Automatic Equalization
Set-up the frequency of the auto equalize function. Available options are between 1 and 250 days:
1 = daily
2 = every other day
...
250 = every 250 days
Equalization is typically used to balance the cells in a lead battery, and also to prevent stratification of the electrolyte in flooded batteries. Whether (automatic) equalization is necessary, or not, depends on the type of batteries, and their usage. Consult your battery supplier for guidelines.
When the Automatic equalization cycle has initiated, the charger applies an equalization voltage to the battery as long as the current level stays below the equalization current percentage setting of the bulk current.
Duration of the Automatic equalization cycle
In the case of all VRLA batteries and some flooded batteries (algorithm number 0, 1, 2 and 3) automatic equalization ends when the voltage limit (maxV) has been reached, or after a period equal to (absorption time/8) - whichever comes first.
For all tubular plate batteries (algorithm numbers 4, 5 & 6); and also for the user-defined battery type, automatic equalization will end after a period equal to (absorption time/2).
For the Lithium battery type (algorithm number 7), equalization is not available.
When an automatic equalization cycle is not completed in one day, it will not resume the next day. The next equalization session will take place according to the interval set in the 'Auto Equalization' option.
The default battery type is a VRLA battery and any user-defined battery will behave as a tubular plate battery with regard to equalization.
Equalisation stop mode
Set how the equalisation will end. There are two possibilities, first is if the battery voltage reaches the equalisation voltage and the second is on fixed time, where the maximum equalisation duration is used.
Maximum equalisation duration
Set the maximum time that the equalisation phase will last.
Tail current
Set the current threshold that will be used to finish absorption phase before the maximum absorption time expires. When the battery current gets below the tail current for one minute, the absorption phase will end. This setting can be disabled by setting it to zero.
Temperature compensation
Many types of battery require a lower charge voltage in warm operating conditions, and a higher charge voltage in cold operating conditions.
The configured coefficient is in mV per degree Celsius for the whole battery bank, not per cell. The base temperature for the compensation is 25°C (77°F), as shown in the chart below.
With a temperature sensor installed to the User I/O connection block; the actual battery temperature will be used for compensation; throughout the day.
Low temperature cut-off
This setting can be used to disable charging at low temperatures as required by Lithium batteries.
For Lithium Iron Phosphate batteries this setting is preset at 5 degrees Celsius, for the other battery types it is disabled. When creating a user defined battery the cut-off temperature level can be adjusted manually.
Manual Equalization - Start now
Selecting 'Start now' on 'Manual equalisation' allows manual initiation of an Equalization cycle. To allow the charger to equalize the battery properly use the manual equalize option only during absorption and float periods, and when there is sufficient sunlight. Current and voltage limits are identical to the automatic equalize function. The duration of the equalisation cycle is limited to a maximum of 1 hour when triggered manually. Manual equalization can be stopped at any time by selecting 'Stop Equalize'.
3.12. Connecting to AC PV inverters
The solar inverter includes a built in AC PV inverter detection system. When there is a feedback of AC PV (a surplus) from the AC-out connection port, the solar inverter will automatically enable an AC output frequency adjustment.
While no further configuration is required, it is important that the AC PV inverter is configured correctly to respond to the frequency adjustment by reducing its output.
Note the 1:1 rule of AC PV inverter size to solar inverter size, and minimum battery sizing applies. More information about these limitations are available in the AC Coupling manual, and this document is required reading if using an AC PV inverter.
The frequency adjustment range is not configurable, and includes a built in safety margin. Once the absorption voltage is reached, the frequency will increase. So it is still essential to include a DC PV component in the system for complete battery charging (i.e. float stage).
It may be possible to adjust the power output response to various frequencies on your AC PV inverter.
The default configuration has been tested and works reliably with the Fronius MG50/60 grid code configuration.