Narada VRLA Series User manual

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VRLA 
(VALVEREGULATEDLEADACID)BATTERY
Installation, Operation and Maintenance
Manual 12V & 2V
HIGH RATE (HRL)
RESERVE POWER
(FM, GFM, NDT, NDF, CPL, EOS)
PURE LEAD (NPL, UDS)
HIGH TEMP (HTB)
Version：V2.3

VRLA Installation, Operation & Maintenance Manual
2 Subject to revision without prior notice. E.&.O.E V2.3
Important Safety Instructions
Please read this installation, operation and maintenance (IO&M)
manual carefully. All VRLA cells and batteries from Narada are
safe when handled and operated in accordance with the
precautions and recommendations outlined in this document.
ONLY PERSONNEL TRAINED IN THE SAFE HANDLING OF
BATTERIES AND OTHER LIVE ELECTRICAL EQUIPMENT
SHOULD BE ALLOWED TO WORK ON ANY BATTERY
SYSTEM.
 DO NOT attempt to remove any component or part
of the battery. VRLA batteries are not repairable.
 VRLA batteries are fully recyclable. Contact your
nearest Narada service center to safely dispose of
your spent battery
 DO NOT SMOKE, have a naked flame or cause a
spark near a battery
 DO NOT use any organic solvent to clean the battery
 ALWAYS use insulated tools when working on or
near a battery since using an uninsulated tool could
 cause a battery short circuit that can lead to serious
bodily injury
 ALWAYS wear eye protection when working on a
battery
 DO NOT wear a watch or metallic jewelry when
working on a battery as they can cause a short
circuit
 DO NOT charge batteries in a sealed (airtight)
container or enclosure
 In the unlikely event of eye or skin exposure to acid
clean the affected area with plenty of clean water,
then seek medical help
California Proposition 65 warning: Battery posts, terminals
and related accessories contain lead and lead compounds,
chemicals known to the State of California to cause cancer and
reproductive harm, and during charging, strong inorganic acid
mists containing sulfuric acid are evolved, a chemical known to
the State of California to cause cancer. Wash hands after
handling.
1. Receipt of shipment
Examine the batteries received for any signs of physical
damage and that the contents of the shipment agree with the
packing slip. Report any damage or discrepancy immediately
to Narada. Since VRLA batteries contain acid in fiberglass
separators, use rubber gloves when handling a physically
damaged battery.
2. Storage
All VRLA batteries should be stored in a cool, dry place and
away from exposure to sunlight or other sources of heat. Since
batteries lose charge over time they need to be given a
freshening charge at regular intervals. These intervals are
determined by the storage temperature; batteries lose charge
faster at warmer temperatures – storage time is cut by 50% for
every 10ºC (18°F) rise in temperature. The maximum storage
times between freshening charges are given below. Failure to
follow our freshening charge recommendations will void
the warranty of the battery.
Note that batteries must always be fully charged before
they are stored.
VRLA series
Storage
Temperature
Range
Recharge criteria1
Months OCV
HRL / GFM /
FM
0°C to 35°C
(32°F to 95°F) 6 2.10 VPC
NDT / NDF /
AT
-20°C to 40°C
(-4°F to 104°F) 6 2.10 VPC
EOS -20°C to 40°C
(-4°F to 104°F) 12 2.10 VPC
NPL / UDS /
HTBF / CPL
-20°C to 40°C
(-4°F to 104°F) 12 2.05 VPC
HTB -20°C to 40°C
(-4°F to 104°F) 24 2.05 VPC
Ta b l e 1 : Freshening charge and storage criteria
VRLA series Freshening
Voltage
Maximum
Current
HRL / GFM /
FM 2.40 VPC 0.20C20 amp
NDT / NDF /
AT 14.4V 0.20C10 amp
EOS 2.35 VPC 0.20C10 amp
NPL / UDS /
HTBF /CPL 14.4V 0.25C10 amp
HTB 14.4V 0.25C10 amp
Ta b l e 2 : Recharge voltage and current parameters
1 Recharge whichever occurs first; OCV threshold or Months of
Storage
Wear eye protection
Do not short circuit Keep children away
Danger Electricity Danger
Recycle
Do not put battery in the
trash can
Recognized by UL as a
component
Read the manual No smoking, no naked
flame, no sparks

VRLA Installation, Operation & Maintenance Manual
3 Subject to revision without prior notice. E.&.O.E V2.3
3. Installation
 Ambient temperature
VRLA batteries must be installed in clean, dry areas and
away from direct exposure to heat sources such as
sunlight. The optimal operating temperature range for
VRLA batteries is between 68°F (20°C) and 77°F (25°C).
The actual operating temperature range can be as wide
as -40°F (-40°C) to 140°F (60°C). Please consult the
battery’s data sheet for its specific operating temperature
range.
 Ventilation
Although VRLA batteries release minute quantities of gas
during normal operations (the recombination efficiency
is >99%) they must not be installed in airtight enclosures.
The battery enclosure is acceptable as long as it affords
normal ventilation that is sufficient to keep the batteries
cool and prevent the accumulation of hydrogen gas in
case the charger inadvertently overcharges the batteries.
Finally, all batteries must be installed in accordance with
not only the manufacturer’s recommendations but must
also comply with all relevant local, state and federal
regulations.
 To r q u e
It is extremely important to make sure all inter-battery or
inter-cell connectors are torqued to the manufacturer’s
recommended setting, as shown in Table 1. A loose
connection can cause problems such as incorrect charge
voltage at the battery terminals, cable overheating and
unnecessary voltage drops due to higher connection
resistance.
Te r m i n a l
To r q u e
N-m In-lb
M5-F 6±1 53.4±8.9
M6-F / M6-M 8±1 71.2±8.9
M8-F 10±1 89.0±8.9
Ta b l e 3 : Recommended torque values
4. Charging
 Float voltage
The float charge voltages for the various VRLA battery
families at 77°F (25°C) are shown below, along with the
maximum recommended charge currents and the
temperature compensation coefficients. Note that the
compensation coefficient is inversely related to the
temperature – charge voltage must be lowered when the
temperature rises and raised when the temperature drops.
Table 4 below shows the recommended float charging
parameters.
 Equalizing charge voltage
The equalize charge voltages for the various VRLA battery
families at 77°F (25°C) are shown in the following table.
Equalize charging should be used when batteries have
been on open circuit for an extended period of time and
need freshening. (2-3 months or longer, less than
2.13VPC and or have a battery to battery voltage
differential of 0.05VPC or greater). The equalizing charge
voltages listed in Table 4 should be limited to 16 hours.
The charge current for both float and equalizing
charge must be limited to its C5(in amps) to 1.75 VPC.
Ta b l e 4 : Voltage, current and temperature compensation
 Ripple current
Since ripple currents are damaging to batteries and
shorten their life we recommend limiting the ripple content
of the charger to 0.5% RMS and 1.5% peak-to-peak of the
float charge voltage.
5. State of charge (SOC)
The SOC of a battery can be determined by measuring its
open circuit voltage (OCV) using a high quality digital
voltmeter. The battery must have been at rest preferably
for 24 hours (but for no less than 8 hours) before an OCV
reading is taken. Table 5 shows the relationship between
SOC and OCV. Batteries must be recharged once every
6 months during cooler months and every 3 months
during warmer months, or when the OCV drops to 2.10
VPC, whichever occurs earlier. See Section 2 above for
more details.
Volts per cell (VPC) State of charge (SOC)
2.12V or higher 100%
2.09 – 2.10V 80%
2.05 – 2.08V 60%
2.01 – 2.04V 40%
1.97 – 2.00V 20%
Ta b l e 5 : Relationship between SOC and OCV
6. Battery discharge
Batteries should not be overdischarged as it is detrimental
to its life expectancy. To prevent an overdischarge the end
of discharge voltage (EODV) must be limited to a value
based on the discharge rate. A low voltage cutoff should
also be included in the load circuit to prevent an
accidental overdischarge. MPINarada data sheets are
formatted to show only acceptable discharge rate – EODV
combinations. Narada does not recommend discharging
cells to under 1.60 VPC and no longer than 15 min.
Models
Volts per cell (VPC) at
77°F (25°C) Temperature
Compensation
Float Equalize
FM / GFM /
TT / NDT 2.25–2.27 2.35–2.40 ±3mV/cell/°C (±1.7mV/cell/°F)
HRL 2.25–2.27 2.35–2.40
±3.6mV/cell/°C
(±2mV/cell/°F)
HTB
2.24 VPC
at 95°F
(35°C)
2.30 VPC
at 95°F
(35°C)
±3mV/cell/°C
variation from
35°C
NPL / HTBF
/ UDS / CLP 2.25–2.27 2.35–2.40 ±3mV/cell/°C (±1.7mV/cell/°F)
EOS 2.25–2.27 2.35–2.40
±3.6mV/cell/°C
(±2mV/cell/°F)

VRLA Installation, Operation & Maintenance Manual
4 Subject to revision without prior notice. E.&.O.E V2.3
Two other factors are relevant when discussing battery
discharges. First, batteries must not be left in a
discharged state, and must be charged immediately after
a discharge. Second,
MPINarada battery discharge rates are given for a
reference temperature of 77°F (25°C). At temperatures
above the reference the capacity increases at the
expense of life, while at temperatures below the reference
capacity diminishes and extends battery life. Please refer
to industry standard IEEE 1188 for more information on
the effect of temperature on battery capacity.
7. Maintenance and record keeping
MPINarada VRLA batteries do not require periodic
watering. However, for optimum life and performance they
must be kept clean; cleaning should be done with only a
damp cloth, avoiding the use of any organic solvents.
Below are the recommended maintenance procedures.
 Monthly maintenance (Recommended)
 Keep battery room /site clean.
 Check each battery for cleanliness and look
for signs of damage due to overheating,
particularly at and around the terminals and
on the cables.
 Record battery room /cabinet ambient
temperature.
 Measure and record the total string float
voltage and float charge current at the
closest point to the battery or battery string
termination. The string voltage should read
(N × Recommended float voltage), where N
is the number of cells in the series string.
 Quarterly maintenance (Recommended)
 Perform monthly maintenance procedures
 Measure and record voltage of each
individual on-line battery/cell of the string. If
more than two cells or batteries vary by
more than 0.10 VPC (13V and 6.5V for a 12V
and 6V battery, respectively) equalize the
string as noted in the Section 4 on
equalizing charge. If the problem exists the
batteries may be given the yearly
maintenance noted below.
 Annual maintenance (Required)
 Perform quarterly maintenance procedures
 Check all connections for looseness and
retorque them as necessary.
 Conduct a load test to 30-40% depth of
discharge (DOD), or perform an
impedance /conductance /resistance test
to verify battery change from Baseline or
Reference.
 3-year maintenance (Recommended)
 Perform quarterly maintenance procedures
 Check all connections for looseness and
retorque them as necessary.
 Conduct a load test to 80% DOD or perform
an impedance/conductance /resistance
test to verify battery system capacity.
All of the records should be carefully kept in a logbook as
MPINarada will require all maintenance records in the event of
a warranty claim. The logbook should also record any unusual
activity such as power outages, rectifier/UPS alarms, etc.
After sales service
North America:
MPINarada
44 Oak Street, Newton, MA 02464
Tel: [phone]
www.mpinarada.com
[email protected]
China:
NARADA POWER SOURCE CO.,LTD.
No.459 Wensan Road, Hangzhou, Zhejiang, P.R.China
Tel:[phone] Fax:[phone]
www.en.naradapower.com
[email protected]