Flowserve L120 Series Limitorque Actuation Systems - Manual (Page 12)

Limitorque Actuation Systems L120 Series FCD LMENIM1201-04-AQ – 05/15
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4.4.2 Balancing Torque Switch
Item letters correspond to Figure 4.1.
1. Place the actuator in manual mode.
2. Remove the load from the wormshaft spring pack.
3. Note the open and close torque switch settings prior to reinstalling the torque switch.
4. Loosen Screws (A) and position both Pointers (B) at the #1 setting, tighten Screw (A). In this
position the index marks should be aligned.
5. Loosen balancing screws and install the torque switch. The base of the torque switch should be
flush against the compartment and the hole for the mounting screw should be aligned.
6. Install the mounting screw.
7. Tighten the balancing screws.
a CAUTION: The balancing screws should not be touched except during the balancing procedure.
The switch is now balanced and ready for the pointers to be returned to their original settings.
4.5 Geared Limit Switch
a CAUTION: The geared limit switch is not preset at the factory and must be adjusted after the
actuator has been mounted on associated equipment.
• Disconnect all incoming power to the actuator prior to opening the limit switch compartment and
adjusting the switch.
• Consult the relevant wiring diagram for limit switch contact development. All L120 units are
supplied with 16-contact limit switches - four switches on each of the four rotors. Two rotors are
used for end of travel indication. The remaining two rotors may be adjusted for any intermediate
point of travel.
• Do not use abrasive cloth to clean the contacts on the limit switch.
• Do not attempt to repair gearing in the limit switch. Replace entire gear frame assembly if
necessary.
4.5.1 Setting Limit Switch
Set the limit switch as follows. All item letters and piece numbers refer to Figure 4.2.
NOTE: See chart below for maximum number of drive sleeve turns for each unit size. The Intermediate
Shaft (B), shown in Figure 4.2, may take a considerable number of turns before rotor trip occurs.
Table 4.4 – Maximum Number of Drive Sleeve Turns for Standard Four-Gear and Optional Five-Gear
Limit Switches
Actuator Size Four-Gear Five-Gear
L120-10 630 6300
L120-20 740 7400
L120-40 640 6400