GENERAL
Oil temperature indicator, OTI Series 34
The oil temperature indicator series 34 measures the top-oil temperature. It is a standard instrument for cooling, control and protection for all transformer.
Winding temperature indicator, WTI Series 35
The life of the transformer depends on the winding temperature which determines the deterioration of the insulating materials. Due to the high electric potential of the winding, it is not practical to measure the winding temperature directly.
TECHICAL DATA
This product is designed for power transformers. It is s special design for long life, heavy duty and maintenance free control of the oil-（OTI）and winding-（WTI）temperature.
It is made for outdoor mounting directly on the transformer in any climate, tropical as well as arctical. All parts are made of non-corrosive or surface treated material. A powerful measuring system secures the safe and accurate operation of the high capacity contacts. Besides the basic models, described in this bulletin, many options are available. For example:
- transmitter for remote indication
- earthquake-proof execution
- extreme climate execution
- protection class IP 55 or 65 acc. to DIN or IEC.
SPECIFICATION
Casting: Die casted aluminium with two- pack urethane based primer. Clear transparent window of tough polycarbonate plastic. The case is ventilated and weather-proof according to DIN 40050 protection class IP 54
Temperature sensing system: of expansion type (no mercury) and compensated for ambient temperature changes.
Capillary tubing: of copper-nickel with a protective tubing of stainless steel.
Switches: two up to five microswitches, terminal connected as twoway switches(open or close on temperature rise). Electrically separated circuits. Each switch has a dial for setting the contact temperature. Making and breaking capacity:15 A,250 V AC, see last page. Option: switches with magnetic blow out-M.B.O type-with higher DC switching capacity.
Insulation test:2000 V 50 Hz to earth 60 s.
Maximum indicating pointer: resettable from outside with a screwdriver
Instrument operating temperature: for standard execution max.+70,min -40°C
Anti-vibration mountings:included