User Manual

8644/Rockwell - 55
SYSTEM DESCRIPTION
Limitations for use in Zone 2
ATTENTION!
For valve types 6526 and 6527, for use in Zone 2 with temperature class T4, the limitation
(valve switch-off time) T
OFF
≥≥
≥≥
≥ 0.2 s must be strictly complied with under the following
conditions:
• with fast switch-on cycles (valve switch-on time T
ON
< 3 s )
• maximum ambient temperature of 55° C
• maximum permissible overvoltage U
nom
of +10 %
T
OFF
T
ON
Valve switching time
If the valve is switched on for longer than 3 s, there are no limitations for the time until the next switch-on
of the valve.