Frequently Asked Questions

Question	Answer
Should you consolidate your control transformer to a MultiTap or Universal Control Transformer?	When a Multitap Unit might be for you: 1. Transformer will be installed in a device whose source voltage is unknown at time of shipment; 2. Space is not critical (MultiTaps are larger than standard units); 3. You sell to markets with multiple source voltages; 4. Reduced number of parts will offset premium for MultiTap units. When a MultiTap Unit might not be beneficial: 1. High percentage of your business is 240 x 480 source voltage; 2. Space is an issue; 3. Source voltage is always known at time of shipment; 4. Source voltage changes other components in the control circuit; 5. Premium for MultiTap does not get offset by having fewer parts.
Can a 9070 type T or TF control transformer be used in a back (reverse) feed application as a step-up transformer?	No, they cannot. Industrial control transformers terminals are specifically marked “primary” and “secondary”. As such, the National Electrical Code (NEC) and Underwriters Laboratories (UL) prohibit connecting the source to other than the primary terminals. Also, since industrial control transformers utilize compensated windings to accommodate the high regulation inherent in such small transformers, the resulting voltage ratio would be lower than desired. In other words, if a control transformer were reverse fed, the output voltage would be lower than desired.
Does Schneider Electric provide fuses for the primary and the secondary of a 9070 Type TF industrial control transformer?	While the 9070 Type TF industrial control transformer comes with a three-pole fuse block (two rejection-type, Class CC fuses for the primary, and one non-rejection-type, midget fuse for the secondary), Schneider Electric does not provide the fuses. Proper fuse selection is the installer’s responsibility and is dictated by NEC table 450-3(b) and any specific application parameters that exist with any industrial control transformer installation.
My 9070 Type T or TF industrial control transformer has four terminals on both the primary and secondary, but only markings on the wiring diagram of H1and H2 on the primary and X1 and X2 on the secondary. Which terminal do I use?	The nameplate of your Schneider Electric 9070 Type T or TF industrial control transformer clearly marks out that the outside terminals of each side are used for the customer installed wire connections. Schneider Electric makes a standard four- or six-terminal block for various transformer designs for commercial cost effectiveness. With only two terminals being used, it is standard practice for it to always be the outside terminals. Several different transformer voltage and wiring arrangements are shown in this catalog.
How do the 9070-FB3A, 9070-FB2A, and 9070-FB-1A fuse blocks mount on a 9070 Type T control transformer when factory installed? When field installed?	When factory installed on a 9070 Type TF control transformer, they mount on the center of the core on factory installed studs. When field installed by the customer on a 9070 Type T control transformer, they mount over one of the terminal strips using hardware supplied with the fuse block kit. (There are no studs on the 9070 Type T, only on the Type TF.)
Does Schneider Electric offer epoxy encapsulated versions of its 9070 Type T and TF control power transformers?	Schneider Electric does not offer epoxy encapsulated industrial control transformers. The 9070 Type T and TF industrial control transformer is the premier offering in the industry and is suitable for virtually any installation appropriate for a CPT.
What is the sound level for a 9070 Type T control transformer?	Sound levels for general purpose and control transformers are per NEMA ST-20 sound levels. For Type T control transformers, this level is 40dB maximum.
Are replacement jumper kits offered for Schneider Electric’s 9070 Type T and TF industrial control transformers?	Yes. Replacement jumper kits contain two jumpers per kit and must be ordered in minimum quantities of 50 kits. Use kit number 30033-027-53 for Accessory Key I (25–200 VA) and Accessory Key II (25–150 VA). Use kit number 30033-027-54 for Accessory Key I (250–5000 VA), Accessory Key II (200–3000 VA), and Accessory Key III ( 25–3000 VA).
Do 9070 industrial control transformers contain any materials, such as PCBs, lead, or other heavy metals, that would require special disposal means	Schneider Electric 9070 Type T and TF industrial control transformers do not contain any material that would require any special disposal means and can be disposed of in the normal manner. Since the majority of the transformer is built of recyclable material (steel, copper, etc.), Schneider Electric urges the customer to recycle the unit if possible.
What does a “triple rating” mean in terms of an industrial control transformers voltage code?	A triple rating on the control transformer`s voltage code basically means that the transformer is designed to successfully operate at voltages slightly different than the nominal voltage at its full VA capacity. This is done to allow for different voltage systems that require the same voltage ratios, say 4:1 or 2:1. Example: The 9070T250D1 is a triple rated voltage code unit that can supply 250 VA with the following input voltages and the corresponding output: Input: 240 or 480 Output: 120 Input: 230 or 460 Output: 115 Input: 220 or 440 Output: 110
What is the maximum fuse ampere rating that can be used in a factory or field installed fuse block or fuse clip for a 9070 Type T control transformer?	The maximum ampere rating of the fuse blocks and fuse clips offered by Schneider Electric for the 9070 Type T control transformers is 30 amps. If higher fuse ratings are required, then the customer will have to provide the supplementary fuse holder provisions.
On a 9070 Type T or TF industrial control transformer with more than one secondary voltage available, can more than one secondary voltage be utilized or only one?	The capabilities of the various 9070 Type T and TF tranformers vary widely. Some units can only have one voltage out with a given voltage in. Others can have more than one. Contact your Schneider Electric representative for assistance. If a satisfactory model is not available, Schneider Electric has the capability of building virtually any industrial control transformer a customer may need.
What does the CE VA rating mean in selecting a 9070 Type T control transformer?	The CE mark is the official marking required by the European Community for all Electric and Electronic equipment that will be sold, or put into service for the first time, anywhere in the European community. CE VA is the rated capacity of the control transformer according to the CE standard. By bearing the CE marking, a transformer can be sold into any of the participating European countries without having to first clear with that country whether it will accept the UL rating.
An installer had been told by an electrical engineer to ground a 9070 Type T control transformer’s frame to the enclosure with a star washer. If this is so important, why does Schneider Electric plate the base of the transformer?	The 9070s base is plated to keep it from rusting. Schneider Electric does not provide grounding provisions on transformer, as grounding is the responsibility of the installer per NEC requirements.
Does a Schneider Electric 9070 Type T or TF industrial control transformer have any continuous overload capacity? What about momentary overloads due to high inrush loads, such as may occur with a coil on a contactor?	Transformers are 100% rated devices. As such, they do not have any continuous overload capacity. They are specifically designed for momentary currrent draw in excess of their rating for high inrush type loads.
Does a 9070 Type T or TF transformer need to have its impedance listed on its nameplate to be used in any particular area in the world?	Industrial control transformers do not have to list their impedance on their nameplate. They can be used anywhere in the world where their UL, CSA, or CE listing allows, or where they are allowed by the local jurisdiction.
What is the difference between an old 9070 Type K transformer and a new 9070 Type T?	The CE rated, NOM approved Type T transformer replaces the Type K, which is no longer available. The Type T matches the Type K in function and form, but not necessarily in fit, i.e., the dimensions may vary.
Does Schneider Electric offer finger-safe covers for use with 9070 Type T and TF transformer fuse blocks?	The fuse puller accessories (9070FP1) do offer some protection when used and the fuse is in place, however they do not qualify the block for any additional standards. While the fuse block is CE marked, the fuse puller kit does not comply with European standards for finger-safe, as it does not require a tool to remove it. However, this may not be critical as Schneider Electric does not recommend shipping our fuse block or 9070TF to Europe, as the fuses used there are different than those used in North America. Thus, the customer should supply their own fuse block suitable for the European fuses when the transformer is to be used in Europe.
Can a 9070 Type T control power transformer or a general purpose transformer be used to provide power for 24V lighting, 120V to 24V application?	The NEC requires the transformer feeding the low voltage lighting system to be a part of the UL listed lighting system as assembled by the Original Equipment Manufacturer (OEM). A contractor, distributor, or end user cannot assemble their own low voltage lighting system and comply with the NEC without going through UL. If the OEM has a particular transformer listed in their UL file, then that unit may be used. So if the Schneider Electric 9070 Type T device is part of a lighting system that is UL listed, the answer is yes.