AnsaldoSTS 95 - 3.2. General Maintenance Procedures

General Maintenance and Troubleshooting
3-2 SM 6495, Rev. 7, December 2008
3.2. General Maintenance
3.2.1. Periodic Maintenance
The unit should be checked periodically to see if it is working and within the required guidelines.
While being inspected, the exposed gear teeth and cover hinge pins should be lubricated with white
lithium grease. Units in heavier traffic areas should be inspected and tested more frequently.
Generally, the frequency of maintenance should be determined by the customer, but should not exceed
six months.
If system grounds are detected at the gearmotor, the gearmotor may need to be opened and the dust
removed (Section
3.2.10).
3.2.2. Control Relays
The Model 95 can accommodate both non-vital relays and Vital Plug-In Relay US&S PN-150HD. The
motor control relays should be serviced per the requirements of the particular relay and the
requirements as set forth in AREMA, FRA, and other applicable publications.
3.2.3. Contact Adjustments
Contacts 3 through 6 have a simple contact arrangement; closed when on top of the cam and open
when on the lower portion of the cam. The No. 1 contact has a snap action which controls the motor
control relay when on top of the cam and energizes the relay. The No. 2 position is not used for a
contact set.
CONTACT 1
1. Adjust the contact tip so that it rests flat against the heel contact.
2. The No. 1 contact should have a minimum 0.050” total air gap between the heel contact.
3. The contact pressure should be measured close to the contact tip. The pressure of contact No. 1
should be 1-1/2 to 4 lbs. Heel preloading (heel spring pressure is 1-3 lbs. against the lower portion
of the cam) is necessary for the snap action roller to operate efficiently.
4. Make sure the resistance of each contact does not exceed 0.03 ohms (30 mohms) when closed. If
needed, burnish the contacts with 600 grit sandpaper.
CONTACTS 3 - 6
1. Adjust the contact tip so that it rests flat against the heel contact.
2. Each contact pair is set to a minimum of 0.050” gap when fully open.