Hitachi Microscope & Magnifier S-4800 Manual De Usuario

 

4-

7

Power failure or voltage drop 
below 90 V. 

Check the power supply. 

Pump does not rotate at all. 
The breaker switches off 
immediately.  When turning 
on the switch, pump buzzes 
and does not start. 

Oil highly viscous because the 
ambient temperature is low (below 
9 

°

C). 

Close the suction port and turn 
the switch on and off repeatedly 
to repeat slight rotation or warm 
the pump externally. 

Air is leaking due to defective 
vacuum piping. 

Check for a leaky point and 
repair as required. 

The inside of vacuum pipe is 
contaminated. 

Degas the pipe. 

Pipe is too thin or too long. 

Maximize the inner diameter of 
pipe and minimize its length. 

Vacuum degree cannot be 
enhanced. 

Oil is deteriorated. 

Replace oil. 

Oil is inadequate. 

Add oil. 

Air is leaking through the 
upstream pipe. 

Repair the leaky point. 

Loud noise is emitted. 

∗

  Abnormal sound may occur for approx. 5 to 6 sec at start of 

  evacuation, but this does not indicate a fault. 
Oil is leaking through the drain 
valve (for VR16L). 

Make sure the drain valve is 
closed.    If oil leaks through the 
valve is closed, replacement 
with a new valve is required. 

Oil is leaking through the drain 
plug (for VR16L-K/N). 

Retighten the plug.    If oil still 
leaks, replace the drain packing.

Oil is leaking. 

Oil splashes through the exhaust 
port. 

Adjust oil level of replace the oil 
mist trap (element). 

Pump vibrates abnormally. 

Oil is highly viscous due to low 
ambient temperature (below 9

°

C).

Warm the pump externally. 

 
NOTICE:  If the trouble cannot be remedied by the above procedures, contact your   

 

dealer, because overhaul, cleaning or repair may be required at the specified   

 service 

shop.