Download Final Draft Standards Controllers ed 3

“PROPOSED PHILIPPINE NATIONAL STANDARDS
FOR RENEWABLE ENERGY TECHNOLOGIES”
SOLAR PV SYSTEM COMPONENTS
BATTERY CHARGE CONTROLLERS
GENERAL SAFETY AND
PERFORMANCE REQUIREMENTS
DESIGN QUALIFICATION AND
TEST APPROVAL
JUNE 2006
GENERAL SAFETY AND PERFORMANCE REQUIREMENTS
INTRODUCTION
This proposed standard covers general safety, performance and test requirements for
battery charge controllers (BCC) used in photovoltaic systems.
Note: Safety requirements ensure that electrical equipment constructed in accordance
with these standards does not endanger the safety of person or property when
properly installed, maintained, and used in applications for which it was intended.
SECTION ONE - GENERAL REQUIREMENTS
1. SCOPE
This standard specifies general, safety, performance and test requirements for battery
charge controllers in photovoltaic systems specifically those with rated voltage ratings of
12 and 24 V DC.
2. DEFINITIONS
2.1. Charging current: Amount of D.C. current being delivered by the PV generator to the
battery
2.2. Rated voltage: D.C. voltage over which the charge controller is intended to be
operated
2.3. Hysteresis: The range of voltages in between the switching thresholds within which
switching does not take place.
2.4. Low Voltage Disconnect (LVD): The threshold battery voltage which, when attained,
triggers the disconnection of the load from the battery to protect it from deep
discharge cycles.
2.5. Low Voltage Reconnect (LVR): The threshold battery voltage which, when attained,
triggers the reconnection of the load to the battery.
2.6. PV array: A mechanically integrated assembly of PV modules or panels with a
support structure, tracking and thermal controls, and other components, required
to form a direct-current power-producing unit.
2.7. PV array High Voltage Disconnect (HVD): The threshold battery voltage which, when
attained, triggers the disconnection of the battery from the PV generator to protect
it from overcharging and excessive gassing.
2.8. High Voltage Reconnect (HVR): The threshold battery voltage which, when attained,
triggers the reconnection of the battery to the PV generator.
2.9. Stand-by current consumption: The current consumption of the controller at no load
condition. Also referred to as ‘parasitic load’, it is the current consumed by the
controller internal circuits with no power component activated.
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2.10. Rated Solar Current: The maximum current from the PV array that the controller
can safely handle
2.11. Rated Load Current: The maximum load current the controller can safely handle.
3. GENERAL COMPLIANCE REQUIREMENTS
Battery charge controllers should be designed and constructed such that in normal use
they do not cause danger to the users and surroundings.
In general, compliance for battery charge controllers may be checked by carrying out all
the tests specified and described in Section 2 (Standard Test Methods) of Battery Charge
Controller for Photovoltaic Applications-Design Qualification and Type Approval.
4. MARKINGS
4.1. Battery charge controllers should be clearly marked with the following mandatory
markings:
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
Name, monogram or symbol of manufacturer
Model number or type reference of the manufacturer
Date and place of manufacture
Serial number
Rated voltage
Maximum PV array current
Maximum load current
Terminals identification
Low Voltage Disconnect (LVD) and High Voltage Disconnect (HVD)
Type and current rating of fuse
4.2. Markings should be durable and legible.
The steps for checking compliance are specified in Design Qualification and Type
Approval – Section One – General Requirements – Item 4 – Markings.
5. INDICATORS
5.1. As a minimum, light emitting diodes (LED) should be present in the front panel of
the charge regulator to indicate voltage conditions of the battery. A red LED
indicator may be used to indicate a fully discharged battery and a green LED
indicator for a fully charged battery.
5.2. Other indicators such as but not limited to analog gauges and liquid crystal display
(LCD) may be used in addition to LED indicators.
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SECTION TWO - SAFETY REQUIREMENTS
6. TERMINALS
6.1
Terminals should permit the connection of conductors from each component and
should adapt to the amperage requirement of the PV system.
6.2
Terminals should be prominently marked for polarities for each component in the
PV system.
7. CONSTRUCTIONAL REQUIREMENTS
7.1 The battery charge controller should be mechanically robust and should be
designed such that it minimizes the effects of moisture and temperature
during use and prevents the ingress of insects, dust and water spray.
7.2
Adequately robust means of fixing should also be ensured.
8. BATTERY CHARGE CONTROLLER ENCLOSURE
The enclosure of the battery charge controller should provide sufficient protection to the
controller circuitry from the ingress of water spray, dust and small insects.
9. MOISTURE RESISTANCE AND INSULATION
9.1
The Battery charge controller should be moisture resistant. It should not show any
appreciable damage after being subjected to the insulation test described below.
Before the insulation test, visible drops of water, if any, are removed with a
blotting paper.
Immediately after the moisture treatment, the insulation resistance is measured
1 min after the application of a D.C. voltage higher than the rated voltage.
The insulation resistance should not be less than 2 Mohm.
9.2
Insulation should be adequate between the input terminals bonded together and
all exposed metal parts.
10. POLARITY REVERSAL
To check if the battery charge controller is proof against supply voltage polarity reversals,
operate it with reverse voltage for about 5 minutes at the maximum voltage range. At
the end of this period, the supply is reconnected correctly and the battery charge
controller should operate normally.
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11. SHORT CIRCUIT
The battery charge controller should be adequately protected from short circuit
conditions that may arise from PV array and load.
12. OVER-VOLTAGE
The battery charge controller should be protected from lightning flashes and inductive
over voltage if applicable.
13. CONNECTION SEQUENCE
The battery charge controller should be protected from connection sequence reversals
and should be tested according to the procedure described in the Battery Charge
Controller for Photovoltaic Applications - Design Qualification and Type Approval –
Section 2 – Test Methods.
At the end of this test, the correct sequence of connection of each component to the
battery charge controller is re-connected; and the battery charge controller should
operate normally.
SECTION THREE - PERFORMANCE REQUIREMENTS
14. ELECTRICAL CHARACTERISTICS
Electrical characteristics of the battery charge controller should be faithful to the
manufacturer's data and should be tested according to the test procedures described in
Section 2 of the Battery Charge Controller for Photovoltaic Applications - Design
Qualification and Type Approval.
The battery charge controller should be tested for the following:
a.
b.
c.
d.
e.
f.
g.
Load low voltage disconnect (LVD)
Load low voltage reconnect (LVR)
PV array high voltage disconnect (HVD)
PV array high voltage reconnect (HVR)
Stand-by current consumption
PV solar current
Load current
15. ENVIRONMENTAL CHARACTERISTICS
The battery charge controller should be subjected to environmental and electrical cycling
tests described below to determine potential failures.
The sample is tested for the voltage hysteresis at conditions described in Section 2 of
the Battery Charge Controller for Photovoltaic Applications - Design Qualification and
Type Approval.
At the end of these tests, the battery charge controller should operate normally.
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DESIGN QUALIFICATION AND TYPE-APPROVAL
INTRODUCTION
This standard covers the requirements for the design qualification and type approval of
battery charge controllers used in photovoltaic systems.
SECTION ONE - GENERAL REQUIREMENTS
1. SCOPE
This section lays down the requirements for the design qualification and type approval of
battery charge controllers used in photovoltaic systems suitable for long-term
operations.
2. PURPOSE
To determine the electrical and environmental characteristics of battery charge
controllers. The actual life expectancy, so qualified, of battery charge controllers will
depend on their design, their environment and the conditions under which they operate.
3. SAMPLING
Three battery charge controllers for qualification testing (plus spares as desired) will be
taken at random from a production batch or batches. The battery charge controllers
should have been subjected to the manufacturer's normal inspection, quality control and
production acceptance procedures. The battery charge controllers should be complete in
every detail and must be accompanied by the manufacturers handling, mounting and
connection instructions, including the maximum permissible voltage.
When the battery charge controllers are prototypes of a new design and not from
production, the fact should be noted in the test report (see Section One - Item 9 Report).
4. MARKING
Each battery charge controller should carry the markings specified in General Safety and
Performance Requirements - Section One – Item 4 - Markings:
Compliance is checked by inspection and by trying to remove the markings by rubbing
lightly for 15 seconds with two pieces of cloth: one soaked in water and the other with
petroleum spirit.
Note: The petroleum spirit should consist of a solvent hexane with a maximum of 0.1
volume percentage aromatics content, a kauri-butanol value of 29, an initial
boiling-point of approximately 65°C, a dry-point of approximately 69°C and a
density of approximately 0.68 g/cm3.
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5. TESTING
The battery charge controllers should be subjected to the tests in Figure 1, in the
specified order. The test procedures and severities including initial and final
measurements, where necessary, are detailed in Section 2 – Standard Test Methods.
In carrying out the tests, the manufacturer's handling, mounting and connection
instructions should be strictly observed.
6. PASS CRITERIA
A battery charge controller will be judged to have passed the qualification tests if each
test sample meets the following criteria:
The voltage set points for the deep discharge and overcharge protection does not
exceed 0.5% of the prescribed limit after each test.
No sample exhibited any short-circuit or open circuit conditions during the tests.
There is no visual evidence of a major defect, as defined in Section One - Item 7 –
Major Visual Defects.
The insulation test requirements are met after the tests.
All three (3) samples should pass the tests to be judged as meeting the qualification
requirements. Should one sample fail in any test, a new batch of battery charge
controllers should be subjected to all relevant tests, following the same sequence. If any
one of the battery charge controllers fails, the design will be deemed not meeting the
qualification standard.
7. MAJOR VISUAL DEFECTS
For the purpose of design qualification and type approval, the following are considered to
be major visual defects:



shorted terminals
shorted routes in the printed circuit board
shorted electronic parts in the printed circuit board
8. VALIDITY AND COMPLIANCE MONITORING
The certification of those which pass the design qualification and type approval tests will
have a validity of six (6) months to be renewed thereafter. The test agency should
monitor compliance of the same.
9. REPORT
The test agency must prepare a certified test report of the qualification tests with the
measured performance characteristics, details of any failures, and re-tests. A copy of
this report should be provided to the manufacturer and kept for reference purposes.
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10. MODIFICATIONS
Any change in the design, materials, components or processing of the battery charge
controller may require a repetition of some or all the qualification tests to maintain type
approval.
SECTION TWO - STANDARD TEST METHODS
11. STANDARD TEST CONDITIONS
11.1 Ambient temperature and test room
Tests should be made in a room free of draughts and at room temperature
stabilized to plus or minus 1◦C.
11.2 Test voltage
Unless otherwise specified, the battery charge controller to be tested should be
operated at its design voltage.
12. BATTERY CHARGE CONTROLLER VOLTAGE HYSTERESIS TEST
12.1 LOW BATTERY VOLTAGE HYSTERESIS
Purpose:
To determine the low battery voltage hyteresis of the charge controller
Procedure:
a) Set up the apparatus for low voltage hysteresis test as shown in Figure
2a.
b) Apply 12V at the battery terminals of the controller. Determine if the
current is passing through the load circuit.
c) Decrease the voltage applied at a rate not greater than 0.1 V/s. Continue
until the load is disconnected from the battery. This is the low voltage
disconnect level of the controller.
d) Increase the voltage applied at the same rate as above. Continue until
the load is reconnected to the battery. This is the low voltage reconnect
voltage.
The low voltage disconnect should be set at no more than 10% below the nominal
battery voltage. The cut-in voltage for reconnecting the load should be set at about
5% above the nominal battery voltage.
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12.2 HIGH BATTERY VOLTAGE HYSTERESIS
Purpose:
To determine the high battery voltage hyteresis of the charge controller
Procedure:
a) Set up the apparatus for high voltage hysteresis test as shown in Figure
2b.
b) Apply the nominal voltage required at the battery terminals of the
controller. Determine if current is passing through the load circuit.
c) Increase the voltage applied at a rate not greater than 0.1 V/s. Continue
until the PV module is disconnected from the battery. This is the high
voltage disconnect level of the controller.
d) Decrease the voltage applied at the same rate as above. Continue until
the PV module is reconnected to the battery. This is the high voltage
reconnect voltage.
The high voltage disconnect shall be set at no more than 20% above the nominal
battery voltage. The reconnect voltage for reconnecting the PV generator should be
set at about 8% above the nominal battery voltage.
13. NO-LOAD LOSS TEST
Purpose:
To determine the no-load loss of a charge controller.
Procedure:
a) Set-up the apparatus for no-load loss as shown in Figure 3.
b) Set the variable dc source to the required nominal voltage.
c) Measure the current consumption of the charge controller without load.
The no-load loss of the battery charge controller should not exceed 0.5% of the rated
load current.
14. VERIFICATION OF RELIABILITY OF SERVICE WITH APPLIED FULL PV MODULE VOLTAGE AT
NO-LOAD CONDITION
Purpose:
To determine the robustness and ruggedness of the charge controller when full PV
module voltage is applied at no-load condition.
Procedure:
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a) Set up the apparatus as shown in Figure 4.
b) Increase the voltage applied at a rate not greater than 0.1 V/s until the voltage is
equal to the rated solar generator voltage.
c) Maintain this voltage for about 1 hour.
d) Decrease the voltage applied at a rate not greater than 0.5 V/s. Note any shorted
terminals or shorted routes in the printed circuit board or damaged component.
e) Do voltage hysteresis tests as described in Sections 12.1 and 12.2.
The Battery Charge Controller is subjected to no-load conditions by removing the battery,
allowing the BCC to absorb the short circuit current (Isc) of the solar generator. The BCC
should be able to handle the full current from the solar generator.
The BCC passes if after being subjected to the above-mentioned test still functions
normally.
15. DETERMINATION OF RATED SOLAR CURRENT
Purpose:
To determine the rated solar current capacity of a charge controller.
Procedure:
a) Set-up the apparatus as shown in Figure 5.
b) Increase the voltage applied at a rate not greater than 0.1 V/s until the rated
voltage of the charge controller for high voltage disconnect is reached. Slowly
increase the current until the rated solar current is reached.
c) Maintain this voltage and current for about 1 hour.
d) Decrease the voltage and current applied at a rate not greater than 0.1 V/s. Note
any shorted terminals or shorted routes in the printed circuit board or damaged
component.
The BCC should be able to handle the maximum solar current as specified in the
nameplate rating.
The battery charge controller passes if after being subjected to the test still functions
normally.
16. DETERMINATION OF RATED LOAD CURRENT
Purpose:
To determine the rated load current capacity of a charge controller.
Procedure:
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a) Set-up the apparatus as shown in Figure 6.
b) Increase the voltage applied at a rate not greater than 0.1 V/s until the rated
operating voltage of the charge controller is reached. Slowly increase the current
until the rated load current is reached.
c) Maintain this voltage and current for about 1 hour.
d) Decrease the voltage and current applied at a rate not greater than 0.1 V/s. Note
any shorted terminals or shorted routes in the printed circuit board or damaged
component.
The BCC shall be able to handle the maximum load current as specified.
The battery charge controller passes if after being subjected to the test still functions
normally.
17. SHORT CIRCUIT PROTECTION TEST
Purpose:
To determine the ability of the controller to withstand short-circuit conditions.
Procedure:
a) Short-circuit the load terminals. The BCC should be protected against shortcircuits by a fuse, circuit breaker or by any other means.
b) The BCC should function normally after the fuse is replaced or the circuit breaker
reset by applying the voltage hysteresis tests as described in Section 2 – Items
12.1 and 12.2.
The battery charge controller passes if after being subjected to the test still functions
normally.
18. REVERSE POLARITY PROTECTION TEST, SOLAR GENERATOR
Purpose:
To determine the ability of the controller to withstand reverse polarity effects.
Procedure:
a) Reverse the polarity of the solar generator terminals.
b) The BCC should function normally after the fuse is replaced or the circuit breaker
reset by applying the voltage hysteresis tests as described in Sections 12.1 and
12.2.
The battery charge controller passes if after being subjected to the test still functions
normally.
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19. REVERSE POLARITY PROTECTION TEST, BATTERY
Purpose:
To determine the ability of the controller to withstand reverse polarity effects on the
battery.
Procedure:
a) Reverse the polarity of the battery terminals.
b) The BCC should function normally after the fuse is replaced or the circuit breaker
reset by applying the voltage hysteresis tests as described in Sections 12.1 and
12.2.
The BCC should be protected against reverse polarity, at least, with a fuse, or a circuit
breaker.
The battery charge controller passes if after being subjected to the test still functions
normally.
20. ENVIRONMENTAL CYCLING
The battery charge controller is conditioned for 24 hours at 50% relative humidity and 48
hours at 95% humidity. The temperature of the air at all places where samples can be
located is maintained within 1°C at about 40oC. The sample is tested at these
conditions for the voltage hysteresis as described in Sections 12.1 and 12.2.
At the end of these tests, the battery charge controller should operate normally.
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APPENDIX A - TEST CIRCUITS
Voltage
Hysteresis
No Load
Loss
No Battery
Connection
Maximum PV
Array Current
Maximum Load
Current
Environmental
Cycling
Figure 1. Test Sequence
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Battery Charge Controller
S+
+
S-
B+
B-
L+
Variable
DC load
L-
A
Variable
DC supply
V
-
A
a. Circuit for measurement of load low voltage hysteresis
Battery Charge Controller
S+
S-
B+
B-
L+
L-
4.9 V
-
A

Ohmmeter
Variable
DC supply
V
+
b. Circuit for measurement of PV generator high voltage hysteresis
Figure 2. Circuits for voltage hysteresis measurements
Battery Charge Controller
S+
+
S-
B+
B-
L+
L-
A
Variable
DC supply
V
-
Figure 3. Circuit for measurement of internal power consumption
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Battery Charge Controller
S+
+
S-
B+
B-
L+
Variable
DC load
L-
A
Variable DC
Supply
V
-
Figure 4. Circuit for testing no battery connection
Battery Charge Controller
S+
S-
B+
B-
L+
L-
Variable
DC load
A
A
Variable
DC supply
V
Figure 5. Circuit for the determination of maximum PV module current
Battery Charge Controller
S+
+
S-
B+
A
Variable DC
supply
B-
L+
L-
Variable
DC load
A
V
-
Figure 6. Circuit for the determination of maximum load current
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