MADE TO ORDER

SPECIAL PRODUCTION - MADE TO ORDER

Harbuch Electronics provides a design service for non-standard transformers where an 'off the shelf' model is not suitable, for whatever reason. All these designs and the production information are kept on file for future re-order, which often happens after approval of a prototype.

Specialising in E-I audio transformers and toroidal power transformers, most winding services are available

Toroidal transformers

Power Open construction, 5VA to 5KVA, double & auto wound core sizes 25/40/10 to 180/300/100 encased, 60VA to 7.5KVA, double & auto wound

Audio Open construction, 1W to 1KW E-I transformers

Toroidal inductors

Powdered iron cores, up to 4" OD for phase control switchers

Toroidal current transformers Miniature up to 10VA

E-I transformers

Power                 PCB mount, 1VA to 25VA, open & encapsulated
                           construction chassis mount, 4VA to 600VA, single
                           phase core sizes EI30 to 2" centre limb

Audio PCB & chassis mount, 100mW to 300W low level
ne/mic in metal can or PCB mount

U-I transformers

Power 6VA to 25VA low profile core sizes UI30 & UI39

Toroid Mounting and Core details:

Regulation
This is specified as a percentage of the full-load secondary voltage and is indicative only as numbers and configurations of secondary windings will alter this slightly.

Lead Types

Normally stripped winding wire with PVC sleeving. An overall sleeve is added to all primary leadouts and usually to all secondary leadouts exceeding 100V. The PVC is rated at 85ºC. UL sleeving rate at 105ºC can be fitted on request. The overall sleeve is PVC on basic transformers and silicon rubber coated woven glass on critical application transformers.

Core Diameter

This is measured over the average outside diameter including final mylar wrap but excluding lumps due to leadouts etc. The dimensions given are indications only and can vary due to the diameter of the wire used for secondary windings.

Core Height

This is measured over the average width including final mylar wrap but excluding lumps due to leadouts etc. It is to be expected that there will be some unevenness which will be partially absorbed by the mounting rubbers.

Mounting Kit

This is supplied as part of the transformer assembly. It normally consists of two black neoprene rubber disks, a dished steel disk, a bolt, flat washer and hex nut. The diameters of the disks and the length and diameter of the bolt may vary according to the final construction of the transformer but are generally consistent. The rubber disks are for mechanical isolation only and are not to be relied on for electrical isolation from the mounting surface.

Any electrical isolation must be achieved in the final mylar wrap. Alternative mounting methods are available to order, the most common being a recessed epoxy centre. This allows the transformer with a flat base to be mounted on a PCB, a transformer with a recessed base to be mounted over a dimple stamped into the mounting base and for a low profile for mounting into low profile cases. It also provides a more shock-proof mount for high vibration environments.

Specifications
The power toroidal transformers are listed in PDF format indicate the range of design parameters available and may be ordered 'as is' or modified.

PTT401-PTT456

PTT457A-PTT4107B

PTT4108-PTT4161

PTT4162-PTT4217

PTT4218-PTT4273

PTT4274-PTT4329

PTT4330-PTT4385

PTT4386-PTT4441

PTT4442-PTT4492

PTT4553-PTT4609

PTT4554-PTT4609

PTT4610-PTT4665