8500 Spot Temperature Sensor
The 8500 Spot Temperature Sensor (STS) contains a single, 3-wire element resistance bulb that is designed to measure the temperature of liquids at a single localized area, such as at or near the bottom of a storage vessel or in a pipeline.
Temperature data is digitized at the tank via the local tank gauge or tank gauge transmitter for transmission to a central location, such as the tank farm or refinery control room.
- 18" (46 mm), 36" (91 mm), 48" (122 mm) nominal stem lengths
- 3/4" (19 mm) NPT, 150# or 300# ANSI RF flanged sockets
- 100 Ohm copper or DIN platinum non-inductive wound resistor
- Type 304 stainless steel sockets
- 0.25" (6.4 mm) standard bulb diameter
- Explosion proof aluminum junction box with terminal strip
- Other sizes and configuration options are available
Product temperature is used for volumetric calculation to a reference temperature and is of significant importance in the accurate calculation of liquid inventories in bulk storage tanks. The 8500 STS easily connects to Varec products, including float & tape transmitters (4000 Advanced Technology Transmitter), servo tank gauges (6005 Servo Tank Gauge) and other instrumentation, to provide temperature data that is digitized at the tank for transmission to a central location, such as a refinery or tank farm control room.
Installation
The 8500 STS may be used in a variety of storage tanks and is generally installed in the first course of the tank shell, about three feet (1 m) above the bottom of the tank. It may be used in fixed roof or floating roof tanks, as long as it is below the pin height at which the floating roof rests.
The sensors are manufactured with three lead wires that can be terminated within the conduit box or explosion proof enclosures of a variety of instruments. Since significant errors can result from erroneous temperature data, all spot temperature elements are precisely calibrated at the factory prior to shipment.
High Pressure Applications
In high pressure applications, such as spheres, horizontal cylinders or bullets, flanged models for 150 psig (1 MPa) and 300 psig (2 MPa) service are available.
Construction
The 8500 STS is designed to meet the high quality and long life required by the storage tank industry. For resistance to corrosive attack in most hydrocarbon service applications, the socket is constructed of 304 stainless steel. 316 stainless steel is utilized in the construction of the sheath and hex nipple.
Connection Type and Length
- 3/4 NPT, 18in (45.7 cm) length
- 3/4 B4426NPT, 36in (91.4 cm) length
- 3/4 NPT, 48 in (122 cm) length
- ANSI 1-1/2 150lb RF, 18in (45.7 cm) length
- ANSI 1-1/2 150lb RF, 36in (91.4 cm) length
- ANSI 1-1/2 150lb RF, 48in (122 cm) length
- ANSI 1-1/2 300lb RF, 18in (45.7 cm) length
- ANSI 1-1/2 300lb RF, 36in (91.4 cm) length
- ANSI 1-1/2 300lb RF, 48in (122 cm) length
Element Type
- 100 Ohm copper element to 212 °F
- 100 Ohm platinum (DIN) element to 212 °F
- 100 Ohm copper element to 392 °F
- 100 Ohm platinum (DIN) element to 392 °F
Single Point Spot Bulbs Only
- 100 Ohm copper, 18” (45.7 cm) stem length
- 100 Ohm copper, 36” (91.4 cm) stem length
- 100 Ohm copper, 48” (122 cm) stem length
- DIN platinum, 18” (45.7 cm) stem length
- DIN platinum, 36” (91.4 cm) stem length
- DIN platinum, 48” (122 cm) stem length
Note! If installing in an existing socket, measure the socket’s
inside diameter.
