PRODUCTS UNLIMITED
Dimensions are shown for
reference purposes only.
Dimensions are in inches over
(millimeters) unless otherwise
specified.
Catalog 1308242
Issued 3-03 (PDF Rev, 8-05)
Specifications and availability
subject to change.
www.tycoelectronics.com
Technical support:
Refer to inside back cover.
What is a Transformer?
A transformer is a passive electrical device which is designed to change one AC voltage to another by magnetic induction. It “steps-up” or “steps-down”
voltage in order to match incoming supply voltage from the utility to the voltage required by the user’s end product. Typical USA supply voltages are 120,
208, 240, 277, 480 (and 575 in Canada). Common International voltages include 110, 220, 380, and 415.
What is an Isolation Transformer?
An isolation transformer is a transformer whose primary and secondary windings are separate for the purpose of isolating the circuit from the supply source.
What is an Autotransformer?
An autotransformer has only one winding, which is shared by the primary and secondary circuits. Autotransformers do not provide isolation but offer a
substantial savings when used to obtain small increments of voltage above or below the input voltage.
What is a Class II Transformer?
A Class II transformer is used to supply Class II circuits. Class II transformers have a maximum VA (Volt-Ampere) rating of less than 100 and a maximum
secondary output of 30 VAC. The maximum VA generally offered is 75 and the most common secondary voltage is 24 VAC. No load secondary voltage may
be as high as 29 VAC. All Class II transformers are either inherently or non-inherently limited. This means that the maximum output current of the
transformer is limited, either by the intrinsic coil impedance or by a fuse or circuit breaker. These transformers are designed to meet the requirements of U.L.
1585.
Inherently Energy Limited Transformers - Class II transformers up to 50 VA are “Inherently Limited” which means that the transformer, if overloaded,
will short itself out and fail safely, not requiring a fuse.
Non-Inherently Energy Limited Transformers - 60 thru 75 VA Class II transformers are generally protected by a resettable circuit breaker or a fuse
within the transformer secondary. Without this overload protection, the transformer would not satisfy the safety requirements for a Class II circuit.
What is a General Purpose Transformer?
General purpose transformers include any VA rating along with primary and secondary voltage ratings up to 600 VAC. Although internal fusing is an option, no
fusing is required. However, applicable U.L. specifications may require fusing in the end product. These transformers are designed to meet the
requirements of U.L. 506.
What is Voltage Regulation?
Voltage regulation is the percent of change in the output voltage when the load is reduced from full load to no load while the input voltage remains constant.
What is the effect of a load on a control transformer?
A control transformer is designed to provide rated output voltage at full VA. As the load decreases, the output voltage will go up. Conversely, increases in
load will result in lower output voltages. Typically, the smaller the VA size of the unit, the greater difference there is between no-load and full-load voltage.
Transformers...Questions and Answers
Part Numbering System
Typical Part No. B4000 – 01 E 07 BB 999
1. Series:
4000 = Class II (UL 1585) inherently protected or internally fused. 4500 = Autotransformer.
4001 = Class II (UL 1585) externally fused. 4600 = 60 Hz. only
4100 = No UL or CSA approval. 4700 = General Purpose (UL 506).
2. Packaging:
– = Bulk Pack Y = Individual Box
3. Primary and Secondary Voltages:
Primary V Secondary V Primary V Secondary V
01 = 120 24 09 = 208/240 24
02 = 240 24 13 = 208/240/480 24
03 = 277 24 20 = 120 12
04 = 480 24 51 = 380/415 24
05 = 120/208/240 24 78 = 575 24
4. VA and Series Dimension:
VA Rating Series Size VA Rating Series Size
A = 10 3/4” (19.05mm) AW = 50 7/8” (22.22 mm)
C = 20 3/4” (19.05mm) L = 60 15/16” (23.81mm)
M = 30 3/4” (19.05mm) J = 75 15/16” (23.81mm)
E = 40 7/8” (22.22 mm) K = 100 1 1/4” (31.75mm)
V = 40 3/4” (19.05mm) Z = 150 1 1/4” (31.75mm)
5. Stack Thickness and Fusing (Generally determined at factory):
19 = 0.5” (12.7mm) thick. 07 = 0.875” (22.225mm) thick. 15 = 1.00” (25.4mm) thick.
02 = 0.625” (15.875mm) thick. 04 = 1.00” (25.4mm) thick. 18 = 1.25” (31.75mm) thick.
6. Mounting and Termination:
Mounting Termination Mounting Termination
K = Foot Mount Leads AE = Foot Mount QCs on Top
BC = 4” (101.6mm)foot Screw / Leads BB = Foot Mount QCs on One Side
G = Panel Mount Leads AB = Foot Mount QCs on Other Side
7. Customer ID Suffix:
000-999 = Factory assigned customer ID
Example: 4000-01E07BB999 This part number is a Class II transformer with a 120V primary and 24V secondary. It is 40VA and inherently energy limited. This
is a foot mount transformer with quick connect terminals (line & load) exiting out of the same side of the transformer cover.
Note: This is a partial listing only. Consult factory for your specific requirements. All combinations of voltage and VA may not be available.
This chart illustrates a breakdown of our part numbering system on a few of our most popular models. Consult factory for your specific requirements.