16 IQ3 manual – Section: Mounting the Actuator
6.4 Handwheel Sealing
Ensure that the sealing cap and
O-ring is fitted securely to ensure that
moisture does not pass down the
centre column of the actuator. For
valves with rising spindles a cover tube
may be fitted, this must also be sealed
with an O-ring and secured with cap
screws.
Fig. 6.4.1
Fig. 6.4.2
6.5 IQM Modulating Actuators
The IQM range of actuators are
suitable for modulating control duty of
up to 1,200 starts per hour.
IQM have a dynamic breaking facility
as standard. If mechanical overrun
of the actuator and valve prove to
be excessive for accurate control, the
brake can be enabled. With dynamic
breaking enabled, motor heating
effects increase and therefore the
number of starts may require reducing
to prevent motor thermostat tripping.
Commissioning of the IQM range is
identical to the standard IQ - refer to
Section 8.
6.6 IQL & IQML Linear Drive Unit
Consists of a lead screw assembly
arrangement attached to the base
of the actuator in order to provide a
linear output stroke between 8 mm
(
3
/4 in) minimum and 110 mm (4
1
/4 in)
maximum.
The IQL/IQML actuator can be supplied
with or without a yoke mounting
adaptor. The adaptor consists of four
pillars and a base flange to suit the
valve.
Fig. 6.6.1 IQML with Yoke
Fig. 6.6.2 IQML without Yoke