Seiko Prospex Air Diver’s Chronograph SSC613P1, SSC615P1, SSC617P1, SSC618P1 (Add your watch in the comments below…)
The Seiko caliber V175 (actually marked V175A) is a solar powered chronograph movement. It is a repairable movement with exposed testing pads for checking the electrical components when troubleshooting is necessary.
This caliber is made in Japan and is found in Seiko branded timepieces. This caliber is part of the Seiko Watch Corporation V (VXXX) family/series of solar powered movements.
Some of the topics covered in this caliber listing:
Seiko claims that the caliber V175 will maintain accuracy of +/- 15 seconds per month at normal operating temperatures of about 5C to 35C (41F – 140F).
The V175 is a solar powered movement, meaning the watch is powered by light which reaches the dial and gets converted into electrical energy which is stored in the battery/capacitor. The chart below shows how long different lights sources can take to fully charge the cell in the V175. This ranges from 150 hours to 5 hours of constant light source. The following excerpt is from the official Seiko manual, it is just a general guideline.
Can you overcharge the V175?
No, this caliber is equipped with an overcharge prevention function.
Words of caution from Seiko:
“When charging the watch, do not place it too close to a photo flash light, spotlight, incandescent light or other light sources as the watch temperature will become extremely high, causing damage to the parts inside the watch. When exposing the watch to sunlight to charge it, do not leave it on the dashboard of a car, etc. for a long time, as the watch temperature becomes extremely high. While charging the watch, make sure the watch temperature does not exceed 60 °C.”
The Seiko V175 has a power reserve of about 6 months when fully charged. Seiko states that this can include using the chronograph for up to an hour per day. There is a low power indicator on the V175. When the power is low, the small seconds hand at 9:00 will skip, ticking at 2 second intervals. During this low power mode, the chronograph will not function until the watch is recharged.
The caliber V175 is a solar powered watch with a manganese titanium-lithium rechargeable capacitor. It is not a normal battery. The number is MT920, or more specifically (because not all MT920 are the same, the MT stands for manganese titanium): part number 302324T (3023-24T) this appears to be updated part for 3023 24H which used to be listed as the part number.
Although there is an instruction manual for dive watches with calibre V175, there is also another instruction manual that combines the following calibers: V172, V174, and V176.
At the time of this post, replacement prices for the cal. V175 were found online in the range of $89.00 USD to $99.00 USD