Eaton Meter Stack Module 800A ...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$1,000.00
$713.67
Eaton Meter Stack Module Three-Phase In Single-Phase Residential 800A 3-Socket Group Metering 120/208V Indoor/Outdoor

Eaton Meter Stack Module 800A Three-Phase to Single-Phase Group Metering System 120/208V Indoor/Outdoor

(No reviews yet) Write a Review

Model: 3MM220RRL

In Stock (leaves warehouse same day if ordered before 3pm ET)

$1,000.00
$713.67
Adding to cart… The item has been added
Free Shipping on orders over $199
We price match and offer bulk discounts! Click Add to Quote. It's quick and easy.
✨
Earn points with this purchase! You can redeem points for giftcards, iPads, XBox's and more. View Rewards
Free Keying on all locks
You may also like

Eaton Meter Stack Module 800A Three-Phase to Single-Phase Group Metering System 120/208V Indoor/Outdoor

Professional Multi-Unit Electrical Metering Solution

The Eaton Meter Stack Module delivers reliable three-phase to single-phase power distribution with 800A capacity for group metering applications. This UL Listed system features aluminum bus construction and five-jaw configuration for professional indoor/outdoor installations at 120/208V service voltage.

Professional Features & Benefits

  • 800A Bus Rating: High-capacity aluminum bus system provides robust power distribution for demanding multi-unit applications.
  • Three-Phase to Single-Phase Conversion: Efficiently converts three-phase input to single-phase output with A-B phase balance for residential metering.
  • Five-Jaw Configuration: Multiple jaw design accommodates comprehensive group metering requirements with professional connection reliability.
  • Indoor/Outdoor Rating: Versatile enclosure design suitable for both interior and exterior installations with weather-resistant construction.
  • UL Listed Certification: Meets rigorous safety and performance standards for code compliance and professional installation confidence.
  • Ringless Security Design: Enhanced security features protect metering integrity while maintaining accessibility for authorized personnel.
  • Group Metering Capability: Designed specifically for multi-tenant applications requiring centralized metering and distribution management.

Technical Specifications

  • Bus Material: Aluminum
  • Bus Rating: 800 A
  • Bypass: None
  • Certifications: UL Listed
  • Interrupt Rating: Depends on selected main circuit breaker
  • Number Of Jaws: Five-jaw
  • Phase: Three-phase in, single-phase out
  • Phase Balance: A-B
  • Product Details: Group Metering
  • Security: Ringless
  • Voltage Rating: 120/208V

Professional Applications

  • Multi-Unit Residential Properties
  • Apartment Complexes
  • Condominium Buildings
  • Mixed-Use Developments
  • Commercial Multi-Tenant Facilities
  • Student Housing
  • Senior Living Communities

Why Choose Eaton Quality?

Eaton meter stack modules provide dependable electrical distribution with UL Listed safety certification and professional-grade aluminum bus construction. The ringless security design and indoor/outdoor rating ensure long-term reliability in diverse installation environments.

Manufacturer Resources

Spec Sheet

Product Specs

Bus Material:
Aluminum
Bus Rating:
800 A
Certifications:
UL Listed
Interrupt Rating:
Depends on selected main circuit breaker
Number Of Jaws:
Five-jaw
Phase:
Three-phase in, single-phase out
Phase Balance:
A-B
Product Details:
Group Metering
Security:
Ringless
Voltage Rating:
120/208V
Department:
Electrical
Product Group:
Power Distribution
Product Type:
Meter Stack
Product Subgroup:
Metering & Meter Sockets

Eaton 3MM220RRL – Frequently Asked Questions

1) Will an Eaton 3MM meter stack work if my building service is three-phase but the apartments need single-phase power?
That is exactly what the Eaton 3MM meter stack module is built for. It takes a three-phase feed in and delivers single-phase power out to each metered tenant socket, using A-B phase balance so the load spreads across the incoming phases rather than piling onto one leg. Service voltage is 120/208V. So a garden-apartment or condo building fed with a 208Y/120 three-phase service can meter individual dwelling units on standard single-phase 120/240-style residential loads without a separate conversion setup.
2) How many tenant meter sockets can I get on an Eaton 3MM meter stack module?
Socket counts run 2, 3, 4, 5 and 6 per module. At 125A per tenant position you can order any of those five counts (3MM212RRL, 3MM312RRL, 3MM412RRL, 3MM512RRL, 3MM612RRL). At 200A per position the choices are 2, 3 or 5 sockets (3MM220RRL, 3MM320RRL, 3MM520RRL). Bus rating on the stack is 800A, which is what limits how much you can hang off it once you total the tenant positions.
3) Do I order the 125A or the 200A version of the Eaton meter stack?
The amperage choice is the per-tenant socket rating, not the stack rating. 125A covers typical apartment and condo units; 200A is what you specify when a unit has electric heat, EV charging, or a larger single-family-size load. Both sit on the same 800A aluminum bus. One thing to know before you spec: the 200A build is offered in 2, 3 and 5 socket modules, while 125A is offered in 2, 3, 4, 5 and 6. If you need a 4 or 6 position group at 200A, you will be splitting it across modules.
4) Is the Eaton 3MM meter stack ringless or ring-type, and will my utility accept it?
Ringless. The meter socket covers on the 3MM stack retain the meter without a sealing ring, which is what most utilities in ringless territory require. Utilities are split on this, and it is not interchangeable in the field, so match the ringless requirement to your serving utility's meter specification before the order goes in. The RRL suffix on the part numbers (3MM320RRL, 3MM520RRL and the rest) is the ringless designation.
5) Is the Eaton 3MM group metering stack five-jaw or four-jaw?
Five-jaw. That is the configuration used for single-phase network metering off a 120/208V three-phase source, where the fifth jaw carries the additional phase connection a four-jaw socket has no place for. It matters because a four-jaw meter will not seat correctly in a five-jaw socket, so the utility meters set on this stack have to be the five-jaw type.
6) Does the Eaton 3MM meter stack have meter bypass?
No bypass. The 3MM stack is a non-bypass design, which means a meter has to be pulled to de-energize a tenant position and there is no lever or bypass horn to keep a unit hot while the meter is out. If your utility requires bypass at each socket for meter changes, or you want to swap meters without dropping tenant power, this is the wrong stack and you need a bypass-equipped meter stack instead.
7) Will the Eaton 3MM stack work on a 480V or 120/240V service?
No. The 3MM meter stack is rated 120/208V and that is the only service voltage it is built for. A 480/277V service needs a transformer ahead of it, and a 120/240V single-phase service is a different animal entirely, since this stack is designed around a three-phase 208Y/120 input. Confirm the service voltage on the utility's transformer before ordering.
8) Can an Eaton 3MM meter stack be mounted outside on the building wall?
Yes, the 3MM meter stack carries an indoor/outdoor rating, so it can go on an exterior wall of an apartment or condo building as well as in an electrical room. It is UL Listed. Weather exposure aside, the usual siting driver is utility access, since the meter faces have to stay reachable for the serving utility.
9) What is the short circuit interrupt rating on the Eaton 3MM meter stack?
The interrupt rating on the 3MM stack is set by the main circuit breaker you select for it, not by the stack itself. So when the engineer's drawing calls out an available fault current at the service point, that number gets satisfied by the main breaker specification, and the stack follows it. Plan the breaker selection around the utility's available fault current at the service entrance.
10) Is the bus in the Eaton meter stack copper or aluminum?
Aluminum, rated 800A. That is worth knowing for two reasons on the install: the lug terminations on aluminum bus need the specified torque values and, on some jobs, an anti-oxidant compound per the installation instructions, and some institutional and government specifications call out copper bus explicitly. If the spec on the drawing says copper bus, this stack does not meet it.
11) How many apartments can I meter off one 800A Eaton meter stack?
The 800A bus is the ceiling, and how many units it serves depends on the socket rating you choose and the diversified load calculation for your building. Physically, a single module holds up to 6 positions at 125A or up to 5 at 200A, and group metering installations commonly stack multiple modules on the same 800A bus to reach the unit count. The load calculation, not the socket count, is what decides where you stop.
12) Is the Eaton 3MM meter stack right for a mixed-use building with retail on the ground floor?
Only for the residential portion. The 3MM stack converts three-phase to single-phase, so every metered position off it is a single-phase tenant. Retail or commercial tenants that need three-phase power for rooftop HVAC, refrigeration, or three-phase motor loads cannot be served from these sockets, and those units need three-phase metering on a separate stack or individual three-phase socket. Plenty of mixed-use jobs run both, with the 3MM handling the dwelling units above.
How fast can I get the Eaton 3MM220RRL delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Eaton 3MM220RRL come with a warranty?
Absolutely. The Eaton 3MM220RRL is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Eaton 3MM220RRL?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Eaton 3MM220RRL from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
!