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January 7, 2002

Product Release No.:  2002-NPR02

Wall Plug-in “Linear” NiMH and NiCD Battery Chargers

Dynage offers the WB14.2CY, WB14.2DT, and WB14.2ES Series of “smart” wall plug-in, linear-regulated, pulse-type battery chargers for NiMH and NiCd battery packs which have thermistors installed with 10 Kohm @ 25 °C and 29.3 resistance ratio.

The pulse chargers provide multiple methods of fast charge termination.  The primary methods are (1) detecting the maximum voltage slope by mathematically calculating the first derivative of the battery voltage as it is charged and (2) detecting an accelerated increase in temperature slope of the battery pack temperature with the thermistor.  The accelerated rate of temperature rise occurs as the amount of readily chargeable material diminishes at full charge.  Backup methods employed by the  charger for fast charge termination include (1) detecting a flattening in the voltage slope, ?v or negative ?v, to stop the fast charge, (2) reaching the maximum battery temperature set point, and (3) using a timer to limit the duration of fast charge.

The chargers use a very battery-friendly pulse charge algorithm similar to chargers specifically used by NASA for critical applications.  The pulse charge algorithm provides a four-stage charge sequence, namely, soft start, fast charge, topping charge, and maintenance charge.  A very short duration discharge pulse is provided after each positive charge current pulse into the battery to favorably condition the battery.

LED indications (3 of them) are provided as follows:
     Soft Start and Fast Charge:  Yellow LED is “on”.
     Topping Charge and Maintenance Charge:  Green LED is “on”.
     Battery Temperature Maximum or Minimum is Exceeded:  Red LED is “on”.
Three (3) different wall plug-in sizes are offered in the CY, DT, and ES case sizes.

Standard catalog charger models are available for battery packs ranging from “4 cells” to “11 cells” in series in 1-cell steps.  Custom models can be made for specific customer requirements involving a battery pack with more than 11 cells in series.

Charge rates of C/1, C/1.5, C/2, C/2.5, C/3, C/4, C/5, C/6, C/7, C/8, or C/9 can be specified for the charging of NiMH and NiCd batteries..  Additionally, NiCd batteries may be able to be charged at rates of 4C, 2C, and 1.3C, but check the battery specifications before trying to recharge NiCd batteries faster than the C/1 (1 hour) rate.  Charge current ratings of the three (3) different wall plug-in charger sizes (CY, DT, and ES) are given below for each battery pack voltage rating:

      0.25, 0.50, and 0.83 amperes (or 250, 500, and 830 mA) for 4-cell battery packs
      0.20, 0.40, and 0.67 amperes (or 200, 400, and 670 mA) for 5-cell battery packs
      0.17, 0.33, and 0.56 amperes (or 170, 330, and 560 mA) for 6-cell battery packs
      0.14, 0.29, and 0.48 amperes (or 140, 290, and 480 mA) for 7-cell battery packs
      0.13, 0.25, and 0.42 amperes (or 130, 250, and 420 mA) for 8-cell battery packs
      0.11, 0.22, and 0.37 amperes (or 110, 220, and 370 mA) for 9-cell battery packs
      0.10, 0.20, and 0.33 amperes (or 100, 200, and 330 mA) for 10-cell battery packs
      0.09, 0.18, and 0.30 amperes (or 90, 180, and 300 mA) for 11-cell battery packs

     Note:  As an example, select a charger and a battery pack from the listing shown above.  Select a charge current rating of   0.33 amperes (or 330 mA)  for a 10-cell battery pack.  The charger can recharge the 10-cell battery pack (12 v @ 1.2 v/cell) with an AH rating of 2900 mAH in about 9 hours (C/9 charge rate) or a smaller battery with an AH rating of 1300 mAH in about 4 hours (C/4 charge rate) or an even smaller battery with an AH rating of 330 mAH in about 1 hour (C/1 charge rate).  The C rate is to be selected to match the charger to the battery pack at the time of ordering to allow the manufacturer to set the internal timers of the charger accordingly before shipping the charger.
Input voltage ratings that are available are 120 vac/60 Hz or 100 vac/60 Hz (Japan), by model selection.  The input plug on the wall plug-in is a 2-prong North American plug.

Output cord is 6 ft long, 3-conductor, two conductors for output power and the thermistor is connected between the 3rd conductor and the minus (-) output power conductor.  The connector options at the end of the cord are listed below:
     Stripped ends (customer will install connector).
     DIN connector.
     Mini-DIN connector.
     Others (upon request).

Pricing examples for one-shot quantity deliveries are given below:

                                                     500-999     100-249      1 - 9
     WB14.2CY Series:                 $  10.35      $  16.10     $  23.00
     WB14.2DT Series                  $  13.05      $  20.30     $  29.00
     WB14.2ES Series                   $  15.75     $  24.50     $  35.00

     Note:  Above prices are subject to change without notice.

See the Dynage web site at

For more information contact:
Philip Dooley

Voice/Fax : 860-875-4455

12 - 8p.m. Eastern    

Web Site:

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