Burkert Type 8642 - Manual (Page 7)

6 - 8642
english
3 GENERAL DESCRIPTION
I/O Box for driving process valves with 6520 and 6521 NAMUR type valves:
• Driving of four Type 6520/6521 valves (PTB No. Ex-97.D.2089x)
• Connection of two sensors per valve
NOTE The line resistance to the sensors and valves shall be not more
than 20
Ω for a max. cable length of 30 m.
The values of the capacity and inductance are specified in the
conformity certificate.
Use only shielded cable for connecting the sensors and valves.
Note also that the screening must be connected, e.g. at the front
panel of the housing.