Siemens 21-115532-001 User Manual

 

M A I N T E N A N C E  

Page 11

 
This manual does not represent an exhaustive survey of 
maintenance steps necessary to ensure safe operation of 
the regulator. Particular applications may require further pro-
cedures. Should further information be desired or should 
particular problems arise which are not covered sufficiently 
for the purchaser’s purposes, the matter should be referred 
to the local Siemens sales representative. 

 
Basic regulator operation can be checked while the regulator 
remains in service. The output voltage can be monitored from 
the control panel display under the <METER> menu on the 
“Vld” screen. 

• Check the calibration by following the steps in the Basic 

Troubleshooting section of the Accu/Stat control panel 
instruction manual. 

 
• Run the tapchanger several steps in one direction in the 

manual mode until the output voltage is outside of the 
bandwidth. Return the control to automatic mode. After the 
predetermined time delay, the tapchanger motor will be 
observed to return the output voltage in-band. Repeat this 
operation, running the tapchanger in the opposite direction. 

 
• Check the Vari-Amp

 limit switches by attempting to run the 

tapchanger beyond the position to which the switches are 
set. The limit switches should function to open the circuit. 
Note: If the limit switch is set at the maximum 10% range and 
fails to function, the tapchanger will stall against a mechanical 
stop. The motor is designed to stall continuously without 
damage. 

 

 

Failure to properly maintain the regulator can result in 
serious injury, death, or equipment damage. The 
instructions contained herein should be carefully 
reviewed, understood and followed.  
 
To prevent:  
 
The following maintenance procedures should be 
performed regularly: 
 
1. Operational checks. 
 

 

2. Periodic inspection. 

 

Hazardous voltages. Will cause serious injury, death, or 
equipment damage.  
 
To prevent: 
 
Always de-energize and ground the equipment before 
maintenance requiring access to high voltage parts. 

 

Operation of the regulator at extreme tap positions 
could produce line voltages outside of operating limits 
that could result in property damage. 

To prevent: 

Operate the regulator only to judiciously determined 
voltage extremes. 

 

Regulator may have High Internal Pressure. Can cause 
serious injury, death, or equipment damage. 

To prevent: 

Use pressure relief valve to vent regulator before 
untanking. 

 

 
The use of unauthorized parts in the repair of the  
equipment, tampering by unqualified personnel, or faulty 
repair and adjustments can result in dangerous conditions 
which can cause serious injury, death, or equipment 
damage.  
 
To prevent: 
 
Follow all safety instructions contained herein, and contact 
your local Siemens sales representative for replacement 
parts.