contact us for the latest Ordering Guide to help you choose the transformer most suitable for your project
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
Power Open construction, 5VA to 5KVA, double & auto
wound core sizes 25/40/10 to 180/300/100 encased, 60VA to 7.5KVA, double &
Audio Open construction, 1W to 1KW E-I transformers
iron cores, up to 4" OD for phase control switchers
Toroidal current transformers Miniature up to 10VA
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
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.
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.
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.
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.
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.