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Power  Supply  Battery  Repair  and  Troubleshooting  

Description  #   Text  Box   Comments  
1   Begin:  Batteries   Begin  diagnostic  process  for  a  work  order  for  Batteries.  Testing  and  maintenance  is  advised  when  a  device  using  batteries  fails  to  turn  on.  
2   Observe  the  condition  of  batteries.   Are  there  any  signs  of  leaking,  rust,  corrosion?  These  obvious  faults  should  clearly  indicate  any  problems  within  batteries.  
3   Are  batteries  leaking  or  corroding?   If  any  batteries  are  not  found  to  be  in  good  condition,  they  should  be  discarded  and  replaced.  
4   Replace  batteries.  See  step  6  for  secondary  batteries  or  step  20  for  primary  batteries.   The  identified  problematic  batteries  should  be  discarded  and  replaced  following  the  guidelines  for  their  type.  
5   Are  the  batteries  rechargeable?   NiCd,  Lead  Acid,  NiMH,  Li-­‐ion  batteries  are  common  chargeable  batteries.  Lithium  or  carbon-­‐zinc  are  not  rechargeable.  
6   Batteries  are  considered  “secondary  batteries.”   Secondary  batteries  have  the  ability  to  be  recharged.  
7   Is  a  functional  charger  available?   Chargers  typically  accompany  types  of  rechargeable  batteries.  

8   Use  BTA  skills  to  construct  a  charger  for  secondary  batteries  using  a  wall  transformer.  See  box  description  for  further  details.  

If  no  charger  is  available,  use  BTA  skills  to  construct  an  appropriate  charger.  BTA  protocol  states  that  this  can  be  done  using  a  wall  transformer  with  a  female  coaxial  cable  connector.  Transformer  must  match  the  input  voltage  (110  vs.  240  V),  the  output  voltage,  voltage  type  (AC/DC),  and  the  output  current  capacity  of  the  batteries.  If  the  original  charger  is  not  available,  connections  to  the  batteries  can  be  made  by  opening  the  device  and  wiring  in  new  connections.  Alligator  clips  should  suffice.  
9   Ensure  that  the  batteries  are  fully  charged.  Use  a  voltmeter  to  test  output  voltage.   Fully  charge  batteries  before  assessing  their  ability  to  hold  their  charge  over  time.  
10   Do  batteries  output  their  specified  voltage?   Measure  and  note  the  initial  voltage  before  leaving  them  to  sit  overnight.  
11   If  battery  does  not  output  its  specified  voltage  by  70%  after  being  fully  charged,  it  will  need  to  be  replaced.  

If  this  initial  voltage  is  not  at  least  70%  of  its  rated  value  at  full  charge,  it  is  not  acceptable  and  should  be  replaced.    

12   After  charging,  leave  the  battery  out  overnight.  Compare  final  voltage  with  the  initial  voltage.   Let  the  battery  sit  overnight  (connected  to  nothing)  to  assess  its  ability  to  hold  a  charge  over  time.  
13   Do  batteries  discharge  less  than  25%  of  its  initial  voltage?   If  more  than  75%  of  charge  is  maintained,  the  battery  is  suitable  for  use.  
14   Secondary  battery  is  working  properly.  See  power  supply  flowchart  for  further  instructions.  

Move  on  to  the  next  step  of  the  power  supply  flowchart  if  device  still  does  not  turn  on.  Be  sure  to  troubleshoot,  calibrate,  and  appropriately  test  medical  device  before  releasing  to  clinician.  
15   If  battery  discharges  25%  or  more  voltage  overnight,  it  will  need  to  be  replaced.   If  less  than  75%  of  charge  is  maintained,  the  battery  is  not  suitable  for  use  and  will  need  to  be  placed.  

Rechargeable  batteries  will  need  to  be  replaced  with  a  rechargeable  of  the  exact  type  or  of  a  similar  type.  Refer  to  box  description  for  more  details.  
Replacements  should  be  an  exact  match  with  type,  voltage,  and  capacity.  An  imperfect  match  is  permitted  if  substituting  with  a  primary  battery  of  a  larger  capacity  with  same  type  and  voltage.  

17   Can  batteries  be  replaced  appropriately?   Exact  replacements  may  not  be  realistic  or  available.  

If  proper  replacements  cannot  be  made,  use  BTA  skills  to  replace  the  batteries  with  a  wall  transformer.  See  box  description  for  more  details.  

Here  are  some  additional  suitable  substitutions:  
-­‐NiCd  for  NiMH  of  the  same  voltage  and  capacity  –  matching  voltage  takes  priority  
-­‐NiMH  for  NiCd  of  the  same  voltage  and  capacity  –  matching  voltage  takes  priority  
The  only  downside  is  that  NiCd  have  lower  capacities  and  operate  for  shorter  periods  of  time  before  needing  to  be  charged.  

19   Troubleshoot  new  replacement  to  ensure  it’s  working  properly.  Go  to  beginning.   Once  an  appropriate  replacement  or  substitution  has  bee  made,  troubleshoot  device  with  new  battery  solution.  
20   Batteries  are  considered  “primary  batteries.”   Primary  batteries  are  not  reusable  and  cannot  be  recharged.  
21   Use  a  voltmeter  to  measure  the  output  voltage.   Check  the  output  of  the  primary  batteries  as  is.  
22   Is  the  measured  voltage  70-­‐100%   If  voltage  is  less  than  70%  of  its  rated  value,  it  must  be  discarded  

of  its  rated  value?   and  replaced.  
23   Primary  battery  is  working  properly.  See  power  supply  flowchart  for  further  instructions.  

Move  on  to  the  next  step  of  the  power  supply  flowchart  if  device  still  does  not  turn  on.  Be  sure  to  troubleshoot,  calibrate,  and  appropriately  test  medical  device  before  releasing  to  clinician.  

Primary  batteries  will  need  to  be  replaced  with  a  primary  of  the  exact  type  or  of  a  similar  type.  Refer  to  box  description  for  more  detail.  
Replacements  should  be  an  exact  match  with  type,  voltage,  and  capacity.  An  imperfect  match  is  permitted  if  substituting  with  a  primary  battery  of  a  larger  capacity  with  same  type  and  voltage.  

25   Can  batteries  be  replaced  appropriately?     Exact  replacements  may  not  be  realistic  or  available.  

If  proper  replacements  cannot  be  made,  use  BTA  skills  to  replace  the  batteries  with  a  constructed  “battery  pack”  in  series  or  in  parallel.  See  box  description  for  more  details.  

Create  a  battery  pack  by  adding  primary  batteries  in  series  or  in  parallel  to  achieve  the  same  total  voltage  and/or  capacity  ratings.  
-­‐In  parallel:  Maintains  voltage,  Adds  Capacities  
-­‐In  series:  Adds  voltages,  Maintains  Capacities  

27   Troubleshoot  new  replacement  to  ensure  it’s  working  properly.  go  to  beginning.   Once  an  appropriate  replacement  or  substitution  has  bee  made,  troubleshoot  device  with  new  battery  solution.  

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