Chat with us, powered by LiveChat
Filter by Brands

Products Unlimited Transformer 

The Products Unlimited transformer, originally manufactured by Products Unlimited Corporation, Sterling, Illinois, is part of a broader line of electrical controls. Products Unlimited Corporation purchased Arrow Hart Company in 1992. Products Unlimited manufactured industrial electric controls in both A/C and D/C voltages from 20 amp to 1500 amp ratings. The product line included Definite Purpose, NEMA Rated Contactors, Transformers, Magnetic Motor Starters, Replacement Contact Kits, Replacement Coils, and Relays. Subsequently, Products Unlimited Corporation was assumed by TYCO (TE) subsidiary, Tyco Electronics. Therefore, Tyco Electronics now manufactures Products Unlimited transformers under the Tyco Electronic name. Tyco maintains the same high-quality engineering and design Products Unlimited transformers have been known for. Products Unlimited Inc. is best known as a manufacturer of contactors, transformers, and other products and accessories intended for use in HVAC Systems.

Authorized Parts, Inc. is a distributor of Products Unlimited and Hartland transformers. We are the “go-to guys” for electrical controls designed and produced domestically and inventoried locally. Our engineering team, testing capabilities, quality control, customer service, and warehousing professionals focus on meeting immediate demand for transformers, contactors, and auxiliary switches, motor starters, and relays. Order industrial electric controls directly through our online system at:

Understanding Transformers

A transformer is an electrical control consisting of two or more coils of wire used to transfer electrical energy by changing the magnetic field. AC voltages can be transformed, which explains the name transformer, into varying voltages. Transformers are capable of either increasing or decreasing the voltage and current levels. A single-phase voltage transformer has two electrical coils of wire, a Primary Winding, and a Secondary Winding. The primary side inputs power, the secondary side delivers the reduced power. The two coils are separate but wrapped together around a common closed magnetic iron core. The core is made of individual laminations connected together to reduce the core’s losses. Finally, the last transformer basic is its power rating. The power rating of a transformer is obtained by simply multiplying the current by the voltage to obtain a rating in Volt-amperes, or VA. Products Unlimited transformers are rated in VA, larger power transformers are rated in units of Kilo volt-amperes, or kVA. Ideally, the electric power at one voltage/current level on the primary is “transformed” into electric power, at the same frequency, to the same voltage/current level on the secondary side. The VA ranges offered are 20VA, 40VA, 50VA, 60VA, 75VA, 100VA, AND 150VA. See our Products Unlimited Transformer Ordering Code at:


Specifying Products Unlimited Transformers

Transformers are made as custom or standard with many options. First, determine Primary and Secondary voltage windings. Select from VAC voltages 12, 24 120, 208, 240, 277, 460, 480, and 575 voltages for either Primary and Secondary voltages in domestic applications and 110, 220, 380, 415, and 550 VAC voltages for international use. Typically, designs include Isolation transformers, Autotransformers, Class II transformers, Inherently Energy Limiting Transformers, Control Transformers, and General Purpose Transformers in VA volt-amps ratings from 5 VA, 10 VA, 20 VA, 30 VA, 40 VA, 50 VA, 60 VA, 75 VA, 100 VA and 150 VA. With Frequency being 50/60 HZ and 130C Class B insulation. 

All leads are wire size 18 AWG stranded with 2/64” insulation thickness. Standard transformers have 12” total wire length, with a 1/2” bare strip. Standard male quick connect terminals are .250 x .032.

With respect to codes, Tyco /Products Unlimited transformer 4000 Series are Class II (U.L. 1585), inherently protected or internally fused. Tyco /Products Unlimited 4001 transformers are Class II (U.L. 1585) externally fused. 4100 transformers are not (U.L. or C.S.A.) approved. 4500 series are autotransformers. And 4700 transformers are general-purpose transformers (U.L. 506). Tyco /Products Unlimited transformers can be ordered as multi-tap if required. When specifying, consideration must be given to primary and secondary volts, VA rating, number of laminations, stack thickness and fusing and mounting and terminations, which are offered as foot mount with wire leads, 4” mounting plate with wire leads, 4” mounting plate with screw terminals, panel mounts with wire leads, foot mount with quick connect spade terminals, and din rail mount or bracket type. The 57 type offers a combination fan center transformer relay on a 4” plate to (U.L. 1585) guide SWIV2, file E113772, with C.S.A.

How to order Tyco /Products Unlimited transformers  

To order, please select the Products Unlimited transformer part number or Primary Voltage, Secondary Voltage, Volt-Amp rating, VA, and the base configuration and connections. Submit your RFQ for quoting on the Authorized Parts website easy to use the form at:

Shipping Policy 

Online customers of Authorized Parts, Inc. should note U.S. export regulations restrict export or sale of product to Crimea, Cuba, Iran, North Korea, and Syria. Sale items paid for through our checkout, to a country with ultimate destinations at these locations will be provided with a refund for the entire content entered in error for each transaction. We reserve the right to disqualify or sort a buy, or change product we find in violation of export regulations. To learn more details contact Authorized Parts, Inc.  

Open-box Quantities

An advantage to being an online customer at Authorized Parts, Inc. is the flexibility of ordering. Save time by establishing your own account. Shop, select, add to your cart, view, enter your order, checkout, and save money! Customer reviews average (4.5 /5.0) for savings, attention to details, product condition, shipping time, a quantity discount, and returns when necessary. Items can be shipped from stock in open box quantities, an offer that allows the buyer the added ease of buying products in less than box quantities. Products ship within one day. We maintain an image for shipping brand name products error-free, in any quantity, quickly. To learn more about our Open Box offer, or request a quote, contact Authorized Parts, Inc.  


Yes. Other manufacturer’s transformers cross-reference to the Products Unlimited 4000 Series. MARS, Motors and Armatures, White Rogers, Square D, Hartland, and General Electric, are examples of manufacturers with equivalent products. However, not all design features are the same, so care should be taken when evaluating.

Yes, often, they are the same device with a part numbers. One might be made for an Original Equipment Manufacturer, or OEM, the other as a standard off-the-shelf, stock transformer. Send an RFQ, and we will cross-reference it.  

Scroll to Top