1993_tevan water pump override control

This is a rather rare modification to the TEVans battery pump system. The box pictured is one of the original factory modified boxes and is not part of the collection. It is unknown how many of the original 56 TEVans were fitted with this modification.

There are five (5) watering pumps in the TEVan system each addressing two rows of the ten (10) row traction battery pack. There are three (3) battery modules with five (5) cells each in each row. These pumps push distilled water through the modules and when filled, the pumps reverse to clear the watering passages, pushing the excess water back to the reservoir. Among other things, this reversing procedure allows gases to vent to the bubblier system and be exhausted by the battery packs venting fan.

Both NiFE and NiCd TEVans utilize this same watering system.

In Auto mode pumps are programed to water the batteries after every charge cycle. This frequency is a bit too much for the NiFE batteries, which, on the advice of EP engineers, would only call for a watering cycle once every five (5) charge cycles.

A closeup picture.

The collection is currently (c2023) in process of reproducing two of these control boxes for the collections Twins.

The following pictures are c2023 updates showing the new control boxes for the Twins. Having no data, dimensions, wiring schematics, etc. from the original boxes pictured above, there was a bit of estimating and recreating to make the replacement controls. We estimated from the pictures that the original box was 8" x 8" x 4" in size. Our box is 7.5" x 7.5" x 2.6" as the closest stock project enclosure we were able to source.