Mercotac

Mercotac contact details

Head office and manufacturing

6195 Corte del Cedro, #100
Carlsbad, California 92011
United States

Telephone +1 760 431 7723

Email sales@mercotac.com

Website mercotac.com

Show Mercotac headquarters on the map Open in Google Maps →

Contact details as published by Mercotac, Inc., checked 2026-10-30. Specify Motion is not affiliated with Mercotac, Inc..

Mercotac product lines

Who Mercotac is

Mercotac, Inc. is a small US manufacturer of brushless rotating electrical connectors, based in Carlsbad, California. Instead of brushes rubbing on rings, its connectors pass current through a pool of liquid metal that is bonded to the contacts. The result is a very low, stable contact resistance (under 1 mΩ on the models we checked) with no brush wear and very little electrical noise, in a compact unit with only a few conductors.

That makes Mercotac a niche but well-known choice for engineers who need to pass high current, or a clean low-noise signal, across a rotating joint with only one to a handful of circuits: welding positioners, plating and heating equipment, test rigs and rotating sensors.

History and ownership

Mercotac’s About page tells a short story that begins in music:

• 1960s: Bob Leslie and his brother Don Leslie develop a brushless slip ring to remove the crackling noise in the Leslie organ speaker, which Don Leslie invented and built.
• 1978: Bob Leslie sees uses beyond organs and founds Mercotac to sell the connector to industry.
• Today: the company still manufactures in California, sells to what it describes as Fortune 500 companies in the USA and thousands of companies worldwide, and supports overseas customers through distributors.

The legal name is Mercotac, Inc. The website does not state current owners, headcount or turnover, so we have not given them.

Product portfolio

Mercotac organises its range by conductor count. Our series records cover the models that engineers most often specify:

• Model 230: two conductors at 30 A and 250 V, up to 1,800 rpm, under 1 mΩ contact resistance, 200 MHz maximum frequency, rated -29 to +60 °C, with IP51 using the optional boot kit. The 235 is the 500 V version and the 205 a 4 A version.
• Model 1500 (and 1250): single-conductor connectors for 500 A (1500) and 250 A (1250), with the 1500 rated to 300 rpm in a stainless steel body. Smaller one-conductor models (104, 105, 110, 130) cover 4 A to 30 A.
• Model 215-2K: two conductors at 15 A and 2,000 V for high-voltage rotating circuits.
• Models 430, 630 and 830: combinations of two 4 A circuits with two, four or six 30 A circuits, up to eight conductors.
• Versatac: a multi-channel range from 2 to 22 conductors at 20 A and 500 V, which Mercotac says runs faster than its larger multi-channel models.

Mercotac also designs custom products for particular applications.

Technologies and standards

The liquid-metal contact is the defining technology. Mercotac’s technical pages make several points worth knowing at the design stage:

• Larger models generally have lower maximum speeds, so check the rating of the exact model.
• The body should preferably rotate rather than the shaft, mounting eccentricity should stay below 0.005 in (0.13 mm) TIR, and the unit must not be rigidly mounted at both ends.
• Orientation matters: on the Model 230, for example, the marked arrow must not point below horizontal, so mounting attitude belongs in the specification.
• Temperature rise from current, rotation and ambient must be kept within the model’s maximum rating.

Mercotac states that its connectors contain a small amount of elemental mercury. It says they are often exempt from the EU RoHS Directive in large-scale, stationary or professionally installed equipment, but that they cannot be said to conform to RoHS and can only be CE marked by the machine builder. It also notes stricter national mercury rules in Norway, Denmark and Sweden. UK and EU OEMs should check these points with their compliance team before committing. Our guide on how to specify a slip ring covers alternatives, and our high-current slip rings page explains brush-type options.

Industries served

Mercotac describes “a wide range of applications” rather than naming industries. Typical uses include welding positioners, rotating heated rolls and platens, plating, packaging and rotary tables, and test and measurement rigs where low noise matters. See slip rings for welding positioners and slip rings for test rigs.

Points to check when comparing Mercotac connectors

A liquid-metal connector and a brush slip ring behave differently, so compare like for like. Check the speed limit, which falls as models get larger, the permitted mounting orientation, and the temperature rise at full current. If you are replacing a Mercotac part with a brush-type ring, expect a larger body for the same current and allow for brush wear and maintenance. If you are moving to Mercotac, confirm with your compliance team that a mercury-containing component is acceptable in every market the machine will ship to.

Global and UK presence

Mercotac has one site, in Carlsbad, and sells internationally through authorised distributors shown on a map on its ordering page. Customers in countries without a distributor can order direct from the USA. The site does not name a UK distributor in its text, so UK buyers should check the map or contact the sales team by email.

What to send when specifying a Mercotac connector

Give the number of conductors, current and voltage for each, speed, mounting orientation, ambient temperature, any signal frequency, the space envelope and whether the body or the shaft rotates. Confirm early whether a mercury-containing part is acceptable for your market.

Specify Motion is independent of Mercotac. Our engineers can help source Mercotac products or propose equivalents from our supply network on published figures; see find a replacement or the slip rings hub.

Mercotac history: key dates

1. 1960sBob and Don Leslie develop a brushless slip ring to cut crackle in the Leslie organ speaker
2. 1978Bob Leslie founds Mercotac to sell the brushless slip ring for other applications
3. 2026Still manufactures its connectors in California

Mercotac slip rings

Slip rings

Model 230

Two-conductor brushless rotating connector with liquid-metal contacts, rated 30 A and 250 V, up to 1,800 rpm, with under 1 mΩ contact resistance, 200 MHz maximum frequency and -29 to +60 °C operation.

High-current slip rings

Model 1500 (and 1250)

Single-conductor liquid-metal rotating connector for 500 A at up to 300 rpm with under 1 mΩ contact resistance, in a stainless steel body; the Model 1250 is the 250 A version.

Slip rings

Model 215-2K

Two-conductor liquid-metal rotating connector rated 15 A at 2,000 V, the high-voltage option in the two-conductor range.

Slip rings

Models 430, 630 and 830

Multi-conductor liquid-metal rotating connectors combining two 4 A circuits with two, four or six 30 A circuits (Model 830: 8 conductors in total), with the 430 rated 250 V.

Slip rings

Versatac

Multi-channel liquid-metal slip ring range from 2 to 22 conductors at 20 A and 500 V, which Mercotac says runs at higher speeds than its larger multi-channel models.

Frequently asked questions

What is Mercotac's website?

Mercotac's official website is mercotac.com. It has a product selector organised by conductor count, individual model pages with ratings, technical pages on electrical and rotational characteristics, mounting guidance, downloads, a page on EU directives such as RoHS and REACH, and contact and ordering pages.

What is Mercotac's phone number and email?

Mercotac publishes +1 760 431 7723 as its telephone number and +1 760 431 0905 as its fax. Its emails are sales@mercotac.com for sales, techsupport@mercotac.com for technical support and info@mercotac.com for general enquiries.

Where is Mercotac based?

Mercotac is based at 6195 Corte del Cedro, #100, Carlsbad, California 92011, USA. The company says it still manufactures its brushless slip rings in California, and its About page mentions a recycling programme and solar energy at the facility.

Who owns Mercotac?

Mercotac, Inc. was founded in 1978 by Bob Leslie, who developed the brushless slip ring with his brother Don Leslie. The website does not state current ownership, a parent company or shareholders, so we have not stated more than that.

Can I buy Mercotac connectors in the UK?

Mercotac sells worldwide through authorised distributors shown on a map on its ordering page, and says customers in countries without a distributor can order direct from the USA. Its pages do not name a UK distributor in text, so UK buyers should check the map or contact sales@mercotac.com.

Do Mercotac connectors contain mercury?

Yes. Mercotac states its connectors contain a small amount of liquid elemental mercury. It says they are often exempt from RoHS in industrial uses, but cannot be said to conform to RoHS, and that CE marking rests with the machine builder. Check national rules before specifying them in Europe.

Sources

1. Mercotac: About
2. Mercotac: Contact
3. Mercotac: Ordering
4. Mercotac: EU directives
5. Mercotac: Home page
6. Mercotac: One-conductor models
7. Mercotac: Two-conductor models
8. Mercotac: Four-conductor models
9. Mercotac: Six-plus conductor models
10. Mercotac: Model 230
11. Mercotac: Model 1500
12. Mercotac: Versatac
13. Mercotac: Rotational characteristics

Figures are summarised from the sources above and from manufacturers' published data on the date shown. Always confirm against the current datasheet for your exact part.