DPT145 — multiparameter dew point, pressure and density transmitter for SF6
DPT145 is a multiparameter transmitter for online monitoring of dew point, pressure and density of SF6 gas in GIS and circuit breakers. It has an RS-485 digital output with the Modbus protocol. The device is being discontinued, and the item is kept for replacement and servicing of the installed base.
- Measured quantities
- dew point, pressure, temperature
- Calculated quantities
- SF6 density, normalised pressure, dew point at atmospheric pressure, ppm
- Output
- RS-485 Modbus
- Features
- extended dew point range; no sampling and no SF6 release; frequent calibration not needed
Price, availability and lead time on request. We help with analogue selection, customs clearance and delivery.
Description
DPT145 continuously monitors the quality of SF6 gas in gas-insulated equipment, in GIS, circuit breakers and other power transmission and distribution equipment. SF6 keeps its insulating properties only with a minimum content of water vapour. Moisture degrades the insulation and promotes the formation of secondary decomposition products, which can cause flashover and equipment failure. Moisture monitoring in SF6 is therefore part of the basic monitoring of gas-insulated substations.
The device simultaneously measures the dew point, pressure and temperature of the gas. From these data it calculates four more quantities: SF6 density, normalised pressure, dew point referred to atmospheric pressure and volumetric moisture concentration in ppm. Direct measurement of normalised pressure shows both sudden and minor gas leaks. Online dew point monitoring warns of moisture ingress, which weakens the insulation and accelerates degradation. The latest version of the device has an extended dew point measurement range.
No sampling is needed, so there is no risk of releasing SF6 into the atmosphere. DPT145 is built into the condition monitoring system, and fewer site visits are required. Frequent calibration is not needed, which lowers installation, operation and maintenance costs. The RS-485 digital output with the Modbus protocol simplifies integration into the OEM systems of equipment manufacturers. According to the order form, the probe has a UNF 7/8-14 thread, a shielded PUR or FEP cable is supplied in lengths from 1.5 to 20 m, and a setting for an SF6/N2 mixture is available.
For spot checks the company offers the DM70 portable dew point meter with a sampling cell. The cell measures at operating and atmospheric pressure, needs a minimum amount of SF6 and collects the gas for recirculation. Such a device is convenient when online readings must be compared with an independent measurement.
According to the official website, DPT145 is being discontinued, and the manufacturer does not recommend designing it into new projects. For new sites the company advises contacting its sales department for an alternative, and the SF6 section of the website lists Indigo500 series transmitters nearby. The item is kept in the catalogue for replacement and servicing of the installed base.
Technical specifications
| Measured quantities | dew point, pressure, temperature |
|---|---|
| Calculated quantities | SF6 density, normalised pressure, dew point at atmospheric pressure, ppm |
| Output | RS-485 Modbus |
| Features | extended dew point range; no sampling and no SF6 release; frequent calibration not needed |
| Status | being discontinued (according to the website) |
Request a price and lead time
DPT145 — multiparameter dew point, pressure and density transmitter for SF6. We reply within one business day.
Or email sales@usk.ua or call 044 339-50-20.
Customs codes
| UKTZED (Ukraine) | 9026 20 20 00 |
|---|---|
| HS, 6 digits | 9026 20 |
| CN (EU) | 9026 20 20 |
| HTSUS (USA) | 9026 20 40 00 |
| China customs tariff | 9026 20 90 90 |
Codes are for reference: the final code is determined at declaration for the specific model.
Questions and answers
Which quantities does the DPT145 measure?
Dew point, pressure and temperature of SF6. The device also calculates density, normalised pressure, dew point at atmospheric pressure and moisture concentration in ppm.
What interface does the transmitter have?
An RS-485 digital output with the Modbus protocol, convenient for integration into OEM systems and condition monitoring systems.
Can the DPT145 be specified in a new GIS project?
The manufacturer does not recommend it because the device is being discontinued. The website lists Indigo500 series transmitters nearby, and an alternative is selected together with the manufacturer.
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