Yes, now you can have complete control over your remote power system
from near and from afar. The Energy Management MKII has the ability
to read, log, regulate and control your system from either the front
panel of your SA inverter, a remote keypad, or remote computer, via
a phone line and modem.
The Selectronic Energy Management MKII can be installed into the SE22
inverter (effectively making it SA22), and will provide you with the following features:-
Four General Purpose Outputs
Each of these outputs have the ability to drive a relay that can be
used to control appliances, regulate a solar panel or wind generator,
control a generator etc. Each output can be separately set to operate
a N/O or N/C relay and can be programmed to function as follows:
Regulator
One or more of the outputs can be programmed as a regulator. In this
mode the output acts as a 2 stage regulator with boost, float and equalize.
This allows the voltage on the batteries to rise to a boost voltage,
after which the battery voltage is reduced to a float voltage. Once
each week the regulator goes into equalize mode which allows the voltage
to rise to a higher voltage than boost to enable the equalization of
the battery bank. The boost, float and equalize voltage points are fully
programmable so they can be set to suit your batteries.
When in "Regulator" mode the output can also be set to shunt
mode causing the output to act as a shunt regulator. This allows you
to load dump the excess solar energy or regulate a wind generator.
With more than one output set to regulator mode, each set to a slightly
different voltage, a multistage regulator can be created with just a
few relays.
A range of optional solid state PWM switches is also available which
will interface to this output to give you a PWM controlled regulator.
Generator Control
In this mode the output 1 is used to control your generator. The generator
is controlled by the following conditions:-
a) Low charge in batteries: Output 1 will start the generator
when the percentage charge in the batteries drops to a "LOW"
level or the battery voltage drops below a set "LOW" voltage
setting. A low battery voltage will only start the generator after
a preset delay. This will ensure the generator will not start due
to temporary drop in battery voltage due to momentary high loads or
surge currents. All the levels and the delay are user programmable.
b) High charge in battery: When the percentage charge in
the batteries rises again to a set "HIGH" level or the voltage
of the batteries rises above a set "HIGH" voltage level,
the output will turn off the generator. The voltage on the batteries
must rise above the high voltage setting for a set amount of time
before the generator is turned off. All the levels and the delay are
user programmable.
c) Generator run time limits: If required, the generator
can be set to operate for a minimum time once it has been started.
d) Lock out times: The generator will not start within
the times that have been set. This ensures you are not disturbed by
the generator at times you want peace and quiet.
Change over control
This function can be set when the "generator control" is
selected and can be used to drive a relay to automatically perform the
change over switching from the inverter 240V supply to the generator
240V supply. Once the generator is started, the Selectronic Energy management
MK II can be programmed to wait a preset delay before switching the
generator output to the load. The 240V output of the generator can also
be used to control the change over output. This is achieved by connecting
the output of the generator, via a simple plug pack, into the INPUT
1 of the Energy management. In this way the change over relay can be
programmed to switch back to inverter if the generator fails to start,
or runs out of fuel.
General purpose programming
Each output may be programmed to turn ON, by one of the following
conditions:
a) Input 1: The output will turn on when input 1
voltage goes higher, or lower than a preset point. The user can also
set a programmable delay after which the output will turn on. As an
example, if the level on input 1 is set to 1 volt, the sense is set
to "low" and the delay is set to 5 minutes, the output will
turn on after the voltage on input 1 goes below 1 volt for 5 minutes.
If the voltage on input 1 goes above 1V again before the 5 minute
delay is up, then the delay is reset and the voltage level must go
below 1 volt for 5 minutes before the output is turned on.
This is useful in controlling the output from a limit switch on
a water tank, a solar radiation level indicator, generator warning
lamps etc.
b) Input 2 : Same as for input 1
c) Charge in battery: The output will come on when the
charge in the batteries drops below, or goes above a preset point.
E.g. If the charge level is set to 70% and the sense is set to "high",
the output will come on when the charge in the batteries goes above
70%. If in the above case the sense was set to "low", then
the output would come on when the charge in the batteries drops below
70%.
d) Battery volts: The output will come on when the battery
volts drops below, or goes above a preset point. The user can also
set a programmable delay after which the output will turn on. As an
example, if the level is set to 12.5 volts, the sense is set to "low"
and the delay is set to 3 minutes, the output will turn on after the
voltage on the batteries goes below 12.5 volts for 3 minutes. If the
voltage on the batteries goes above 12.5V again before the 3 minute
delay is up, then the delay is reset and the voltage level must go
below 12.5 volts for 3 minutes before the output is turned on.
e) Time of day: The output will turn on at a set time and
a set day.
The output may be programmed to turn OFF with one of the following
conditions. If the condition that bought the output ON still exists,
then the output will stay on until the condition ends. For example,
if the output is set to come on with low battery charge and switch off
after a duration, and if after this duration the battery charge is still
low, the output will stay on until the charge goes back above the low
charge point:
Input 1: This is the same as the input "ON" setting,
except the output is turned off by the input 1 level.
Input 2 : Same as input 1.
Charge in battery: The output will switch off when the
charge in the batteries drops below, or goes above a preset point.
Battery volts: The output will switch off when the battery
volts drops below, or goes above a preset point, with a preset delay,
as per the battery voltage "ON" condition.
Time of day: The output will switch off at a set time and
day.
Duration: The output will stay on for a preset duration, after
which it will turn off.
Two General Purpose Analogue Inputs
The voltage level on these inputs can be used to control any of the
four outputs or control the inverter. Each of these inputs is also logged
for four weeks allowing the user to log such parameters as solar radiation,
temperature, wind speed and more.
Inverter Control
The inverter can be controlled to come ON with the following:
-
Time: The inverter can be programmed to turn on at a particular
time and day.
-
Charge in battery: Inverter will turn on when the charge
in the batteries reaches a preset high point.
-
Input 1: Inverter "ON" is controlled by the voltage
level on input 1, this is the same as the output control.
-
Input 2: Inverter is controlled by the voltage level on
input 2 as per input 1.
The inverter can be programmed to turn OFF by the following:
-
Time: The inverter can be programmed to turn off at a particular
time and day.
-
Charge in battery: Inverter will turn off when the charge
in the batteries reaches a preset low point.
-
Input 1 : Inverter off is controlled by the voltage level
on input 1, this is the same as the output control with a level
setting, sense setting and delay.
-
Input 2: Inverter is controlled by the voltage level on
input 2 as per input 1.
Current Shunt Inputs
The Selectronic Energy Management MKII can interface to one, two or
three external current shunts. Shunt input one is able to measure both
charge and discharge current at the same time which means only one external
shunt is required in a basic system. This input can interface to either
a 100A 75mV or 200A 75mV current shunt If you wish to take a separate
measurement of your charging sources (e.g. Solar, wind or Hydro) or
keep track of the power used by a particular DC load, then shunt inputs
2 and/ or 3 may be used. These shunt inputs can be individually programmed
to measure either a load or a charging source, and can interface to
either a 50A, 100A or 200A 75mV current shunt.
Logging functions
Four weeks of information is logged within the Selectronic Energy Management
MKII and can be down loaded via the serial or modem connection onto
a computer. The following parameters are logged.
-
Load profile or charge profile from each of the current shunt inputs.
The average current is logged every hour for 28 days. If the current
is a load, the value logged is a positive current. If the current
is a charge current then the number logged is negative.
-
State of charge of the battery. The percentage charge in the battery
is logged every hour for 28 days.
-
The voltage level on Input 1. The average voltage on input 1 is
logged every hour for 28 days.
-
The voltage level on Input 2. The average voltage on input 2 is
logged every hour for 28 days.
-
Generator run time, hours per day. This is logged every day for
28 days.
Modem & Serial Interface
The Selectronic Energy Management MKII has a DB9 outlet which can
be directly connected to either a computer serial port or a standard
Hayes compatible modem with " sleep " mode. The inverter has
a DC output suitable for operating many modern modems. This eliminates
the need to run the modem from an AC plug pack, allowing the modem
to operate even when the inverter is not supplying output. Via the Energy
Management MKII the modem is programmed to answer the phone line between
2 and 19 rings and set to go into " sleep " mode after sixty
seconds of inactivity. The modem therefore may be left permanently connected,
resulting, when not in use, in a small amount of power being drawn from
the system. All parameters and full inverter control is available over
the serial or modem connection.
The Remote Link software will allow users to communicate
with the Energy Management MKII via their personal computer, running
under Microsoft Windows. Once connected the user can view
and control the inverter in the same way as a keypad, as well as down
load any of the logged profiles into a comma delimited file.
These profiles can be directly imported into many spread sheet packages
such as Microsoft Excel for graphing or manipulation of the
data. |
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Remote Keypad Interface
The Selectronic Energy Management MKII can be connected to a remote
keypad to allow you to have all your energy information at your fingertips.
You can also control the generator from the keypad, turning it off or
on as required or set to auto to allow your energy management to take
control.
Typical Application
The following diagram gives an indication of how a Selectronic SE series
inverter with Energy management MKII can be incorporated into a typical
power system.
In this system the Energy Management MKII performs the following functions.
-
Regulates the solar power input to the batteries via a normally
closed relay, or a Selectronic PWM control switch.(R2).
-
Regulates the wind generator via a normally open relay or a Selectronic
PWM control switch (R1).
-
Uses current shunts 2 and 3 to measure and log, separate charge
currents for the wind generator and the solar array.
-
Uses current shunt 1 to measures and log, the battery current used
by the inverter and other DC loads.
-
Control the petrol (or diesel) generator automatically or manually
via the keypad or modem link. The generator would normally be set
to start automatically if the battery state of charge reaches a
minimum acceptable level, recharging the batteries via the charger.

Electrical Specifications
Parameter |
Energy Management MKII |
Sink current on Outputs 1 – 4 (Relay coil current)
|
100mA maximum
|
Voltage on Outputs 1 – 4 (Relay coil voltage)
|
65V maximum
|
Operating voltage range on inputs 1 and 2
|
0-2.5VDC
|
Maximum voltage on inputs 1 and 2 without damage
|
+/- 30V
|
Modem communication interface
|
RS232 via DB9 connector
|
Current capability of the 8V power supply for the modem
|
0.4A maximum
|
Keypad communication interface
|
RS422
|
Keypad power supply
|
Via 8V modem supply
|
Shunt 1 input voltage
|
- 47.5mV to 150mV
|
Shunt 2 and 3 input voltage
|
0 to 75mV
|
Year 2000 compliance |
Fully compliant.
|
Control functions and settings
Parameter |
Range |
Steps/resolution |
1 Delay settings for inputs 1 and 2 when programmed to control
outputs 1 - 4 or inverter on/off.
|
0 - 40 minutes
|
1 minute
|
1 Delay settings for battery voltage when programmed to
control outputs 1 - 4 or inverter on/off.
|
0 - 40 minutes
|
1 minute
|
1 State of charge in batteries setting when programmed
to control outputs 1 - 4 or inverter on/off.
|
0 – 101%
|
1%
|
2 Regulator boost, float & equalize voltage setting
|
12V battery
24V battery
48V battery |
13.0 - 16.8 V
26.0 - 33.6 V
52.0 - 67.2V |
0.1V
0.1V
0.1V |
Generator change over delay setting
|
0 – 250 sec
|
10 sec
|
Minimum generator run time setting
|
0 – 40 minutes
|
1 minute
|
Lockout start time setting
|
0:00 to 23:00
|
1:00 (1hr)
|
Lockout end time setting
|
0:00 to 23:00
|
1:00 (1hr)
|
1 "Time of day" time settings when programmed
to control outputs 1 – 4 or inverter on/off.
|
0:00 to 23:00
|
0:01 (1 minute)
|
1 "Time of day" day settings when programmed to
control outputs 1 – 4 or inverter on/off.
|
Sun to Sat and
ALL (every day)
|
|
3 Current readings on shunt 1
|
200A shunt
100A shunt |
100A to 200A (400A surge)
50A to 100A (200A surge) |
0.2A
0.1A |
3 Current readings on shunt 2 and 3
|
200A shunt
100A shunt
50A shunt |
0 to 200A
0 to 100A
0 to 50A |
0.2A
0.1A
0.1A |
Notes:
-
These can be programmed separately for each of the four outputs
and the inverter control
-
Each output may be programmed to a different boost and float
voltage.
- All current shunts are 75mV.
Energy Management Mk II brochure:

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