Details of the differential gravity remontoire and planetary maintaining power systems.

Planetary maintaining power is the most reliable system for this purpose. It also provides reduction for heavy weights. Normally maintaining power is used only on the time train. However, when electrical winding is employed, maintaining power must be applied to all trains since the motor may be winding at a time when the clock is called upon to strike the bells. In a manual system the human winder would simply avoid winding the strike trains while they are called upon to strike the bells.  The planetary gear system used for maintaining power in this clock uses an additional spur (reduction) gear for each train.  This gear is slightly smaller and mounted on the same arbor in front of the main barrel's ring gear that has internally cut teeth. When winding, the spur gear counter-rotates in the direction of the ring gear, providing a fascinating visual experience.  Planetary maintaining power was not often used for maintaining power in manually wound systems as this was more expensive than alternative systems. Compare with Potts planetary system. However, it is the most reliable and thus favored system in unattended electrically wound systems where human intervention in the case of difficulties is unlikely.