SAM4S Cash Register ER-5115 User Manual

WARNING: First read the-Safety Precautions-section of this manual. If some unforeseen circumstance creates a conflict 

between the servicing and safety precautions, always follow the safety precautions. 

WARNING: An electrolytic capacitor installed with the wrong polarity might explode

. 

1.  Servicing precautions are printed on the cabinet.  

Follow them. 

2.  Always unplug the units AC power cord from the 

AC power source before attempting to: 

 

 

(a) Remove or reinstall any component or assembly 
(b)  Disconnect  an  electrical  plug  or  connector      
(c)  Connect  a  test  component  in  parallel  with  an        
electrolytic capacitor 

3.  Some components are raised above the printed 

circuit board for safety.  An insulation tube or tape 
is sometimes used. The internal wiring is sometimes 
clamped to prevent contact with thermally hot 
components. Reinstall all such elements to their 
original position. 

4.  After servicing, always check that the screws, 

components and wiring have been correctly 
reinstalled. Make sure that the portion around the 
serviced part has not been damaged. 

5.  Check the insulation between the blades of the AC 

plug  and  accessible  conductive  parts  (examples :  
metal panels and input terminals). 

6.  Insulation Checking Procedure:                

Disconnect the power cord from the AC source and 
turn  the power switch ON. Connect an insulation 
resistance meter (500V) to the blades of AC plug. 

The insulation resistance between each blade of the 
AC plug and accessible conductive parts (see 
above) should be greater than 1 megohm. 

7.  Never defeat any of the B+ voltage interlocks.     

Do not apply AC power to the unit (or any of its 
assemblies) unless all solid-state heat sinks are 
correctly installed. 

8.  Always connect an instrument’s ground lead to the 

instrument chassis ground before connecting the 
positive lead ; always remove the instrument’s 
ground lead last. 

1.  Some semiconductor (solid state) devices are easily 

damaged by static electricity.  Such components are 
called Electrostatically Sensitive Devices  (ESDs); 
examples include: integrated circuits and some field-
effect transistors. The following techniques will 
reduce the occurrence of component damage caused 
by static electricity. 

2.  Immediately before handling any semiconductor 

components or assemblies, drain the electrostatic 
charge from your body by touching a known earth 
ground. Alternatively, wear a discharging wrist-
strap device. (Be sure to remove it prior to applying 
power - this is an electric shock precaution.) 

3.  After removing an ESD-equipped assembly, place it 

on a conductive surface such as aluminum foil to 
prevent accumulation of electrostatic charge. 

4.  Do not use freon-propelled chemicals.  These can 

generate electrical charges that damage ESDs. 

5.  Use only a grounded-tip soldering iron when 

soldering or unsoldering ESDs. 

6.  Use only an anti-static solder removal device.  Many 

solder removal devices are not rated as anti-static; 
these can accumulate sufficient electrical charge to 
damage ESDs. 

7.  Do not remove a replacement ESD from its 

protective package until you are ready to install it.  
Most replacement ESDs are packaged with leads 
that are electrically shorted together by conductive 
foam, aluminum foil or other conductive materials. 

8. Immediately before removing the protective 

material from the leads of a replacement ESD, 
touch the protective material to the chassis or 
circuit  assembly into which the device will be 
installed. 

9.  Minimize body motions when handling unpackaged 

replacement ESDs. Motions such as brushing 
clothes together, or lifting a foot from a carpeted 
floor can generate enough static electricity to 
damage an ESD.