dhi installation and use of low-flow vacuum pump kit for molbloc-s pn 401982 User Manual

 

 

Installation and Use of Low-Flow 

Vacuum Pump Kit for molbloc-S

®

 

Instruction Sheet 

 

 

The use of a vacuum pump, connected downstream of 
the molbloc-S

®

, increases the usable flow range of 

each element.  The installation and operation of the 
vacuum should be in accordance with all applicable 
local electrical, plumbing, building, and safety codes.  
This instruction sheet is a guide to the application of 
the vacuum system and use with the molbloc-S and 
molbox mass flow calibration system.  Please follow 
the recommendations and installation information 
provided in the pump’s operation manual published by 
its manufacturer and provided with the pump. 

 

 

Figure 1: Vacuum Pump 

The power cord included in this kit, P/N 103486, is a 
three-conductor plastic original equipment cord, rated 
at 1875 Watts, 15A-125V.  The conductor colors are 
blue, brown, and green with yellow stripe. 

1.  Refer to Figure 1. Locate the terminal box on 

the top of the pump, and remove the two 
screws that hold the cover in place.    

2.  Remove the cover to expose the terminal 

block.   

3.  Unscrew the safety collar and insert the cord 

through the safety collar and into the terminal 
box.  

4.  Refer to Figure 2. Locate terminal one and 

attach the blue wire (neutral) to it.  Locate 
terminal two and attach the brown wire (line) 
to  it.  Locate the earth ground terminal off to 

the side in the terminal box and attach the green 
with yellow stripe wire (earth ground) to it.  

5.  Tighten the safety collar until the power cord is 

captured and cannot be pulled from the 
terminal box.  

6.  Replace the cover and re-install the two 

screws to secure it. 

Figure 2: Wiring the Leybold SV25B Vacuum Pump 

•  The vacuum pump should be located in a place 

where there is adequate ventilation for cooling.  
Consideration of the noise and heat generated by 
the pump should be made.  It might be desirable 
to install the pump in a location outside of the 
laboratory in which the molbloc/molbox system  
is operating. 

•  Caution should be exercised when calibrating in 

gases other than air.  Asphyxiation of personnel 
within a confined space into which the pump 
exhausts is a real threat when calibrating at high 
flow rates.  Venting of the exhaust gas stream 
outdoors or into a large ventilated space is 
recommended.