Frequently Asked Questions

To receive information on any of these questions, click the question.

Do I need to use a waterproof motor for humid environments?

A waterproof motor should be strongly considered anytime the relative humidity is 90% or more. The reason is thermal cycling— as the motor cools the air inside it contracts and the resulting pressure differential acts to draw-in the outside air. Empire Magnetics’ waterproof motors lock out moisture whereas standard shaft seals allow the humid air to come inside and corrode the motor.

Can you modify my low cost motors to make them waterproof?

No. It is not economically feasible to rework an existing low cost product, to a new function or purpose.

Can you design something less expensive?

Yes, based on a firm contract for 10,000 units per year it would be feasible to design and tool up for lower cost production methods.

Is there some way, any way, to get a waterproof motor for about $50 more than the cost of a high volume production motor?

Yes, when waterproof motors are produced in hundreds of thousands of units per year the incremental costs for waterproofing will be on this order of magnitude. We would be happy to accommodate a contract for large volume orders.

How deep can your motors be operated?

Woods Hole Oceanographic Institute (WHOI) tells us they have been using some of our custom motors at a depth of 2000 meters. The Bedford Institute has been using a custom assembly in the North Atlantic where depth was about 2500 feet.

We proposed an assembly for use at 10,000 ft. as a control for cutting off well heads, however a contract was not signed to complete the work.

Can you make a completely sealed unit?

Yes, it is technically feasible to make a motor where only the output shaft and bearings are exposed to the water. The rest of the assembly can be in a hermetically sealed vessel, but saying something is possible is not the same as saying that someone has paid us to do the work.

What are some of the applications?

US Naval Labs has several stainless steel waterproof motor assemblies in the test facility in Washington DC. The US Naval labs in Orlando, Florida have a system using submerged Empire Magnetics motors, resolver and other components in a test tank.

GE Nuclear fuels division has several Empire Magnetics, Inc. radiation hardened and waterproof motors in use for ultrasound inspection devices for reactor certification.

Lockheed-Martin (INEL) has several waterproof motors and motor gearbox assemblies on ultrasound test assemblies.

McDonnell Douglas has waterproof motors on ultrasound test equipment.

Ocean Spray has stainless steel motors on the cranberry juice packaging line.

Foster Farms has stainless steel motors in the meat processing lines. One application is inserting the sticks in corn dogs.

Bedford Institute is using a WP-U42-OFP assembly to operate test equipment in the North Atlantic. At last report the testing was being conducted at 2,500 ft.

Intake Screens, Inc. has the first 6 prototype motor gearbox assemblies working the Sacramento river delta. These screens are used to prevent debris and wildlife from being pulled into the pumps. The solar powered equipment needed waterproof motors for long term submersion to operate the screens.

What waterproof assemblies have you proposed which did not become contracts?

Control assembly for water jet cutters of undersea well heads.

Tractor drive assembly for water jet cleaning of ships hulls. (This unit can remove the paint and other material from the ships hull while being remote controlled by the operator).

Self contained thruster assemblies. A brushless motor, propeller assembly and drive electronics were proposed as thrusters for small submarines. This particular approach provided a smaller, lighter and more efficient assembly than the alternatives.

Brushless pump motors and generators. The typical brushless motor technology is nearly symmetrical. It can be used as a motor to pump water or it may be back driven to be a generator. We were solicited to propose a system which could be used to generate power from tidal flows or river currents.

Two inch diameter pump motors. There is a need for solar powered, two inch diameter pumping systems. High speed brushless motor assemblies can be provided that will do the job very nicely. However, development funding is required.

Hermetically sealed brushed DC motor assemblies. It is possible to make an assembly based on brushed DC motor technology which is totally sealed and submersible. However, since this item is not in high volume production, in small quantities it is not a low cost item.