Fedrel
FM24
Ultrasonic BTU, DI + fabricated steel, 1.6 MPa, 24 VDC, PT100, RS485, IP68, ±1%; remote, PT1000 and power alternatives optional
Fedrel / Thermal energy and BTU meters
FM35
Ultrasonic BTU, battery, PT100, 1.6 MPa, RS485, IP68, ±1%; PT1000 optional
Connection and size scope: 15/20/25/40/50 mm, brass screwed
MODEL OVERVIEW
What the FM35 offers
- Connection and size scope: 15/20/25/40/50 mm, brass screwed
Manufacturer’s documented description: Fedrel product and price list, effective 20 January 2026, pp. 8, 12, 14. Options and qualifications above are retained as stated.
TECHNICAL DATA
FM35 specifications
| Parameter | Documented value |
|---|---|
| Measuring principle | thermal energy btuFedrel product and price list, effective 20 January 2026, 8, 12, 14 |
| Nominal diameter (DN) | 15, 20, 25, 40, 50S17 · 13 |
| Accuracy statement | ±1%; basis not stated in this blockS17 · 13 |
| Connections | BS21 BSP male screwedS17 · 13 |
| Sensor protection | IP68S17 · 13 |
| Power supply | Battery; chemistry/duration not statedS17 · 13 |
| Included outputs | RS485 Modbus RTUS17 · 13 |
| Documented size scope | 15/20/25/40/50 mm, brass screwedFedrel product and price list, effective 20 January 2026, 8, 12, 14 |
| Body material | BrassS17 · 13 |
| Pressure designation | 1.6 MPaS17 · 13 |
| Temperature sensor | PT100; PT1000 optionalS17 · 13 |
Details to confirm for the offered configuration
These parameters are not established as exact-model values in this record. Some may not apply to this technology.
- Q1 m3 h
- Q2 m3 h
- Q3 m3 h
- Q4 m3 h
- Working pressure and temperature
- Approvals and scope
DUTY & SELECTION
Where to consider this type
A water-volume meter tells you how much water passed. A thermal energy meter combines flow with supply/return temperatures and a calculator to determine transferred heating or cooling energy.
Installation and commissioning
Before the meter is selected
- Matched temperature pair, thermowells and minimum ΔT
- Water/glycol composition and concentration
- Flow sensor position and calculator configuration
- Energy units, complete-system uncertainty and output
Before the system is handed over
- Confirm the installation drawing, orientation and access for service.
- Match the actual flow range and permitted pressure loss to the project.
- Record meter serial number, start reading and any output scaling.
- Commission communications against the receiving system and retain the test record.
Reading and communication
Documentation mentions: RS485. These may be optional or specific to a variant.
Discovery tags come from the documented description, including optional capabilities. Confirm inclusion and exact size/configuration.
A connected metering system is five parts: meter → interface or module → network or gateway → software → billing, dashboard or control system. A quotation should name who supplies and maintains each one. AMR-ready equipment may still require separately quoted radio, gateway, head-end and billing software.
Understand pulse, wired and wireless reading ↗Documents and purchase checks
Read the Fedrel technical reference → · Browse the source index
Source: Fedrel product and price list, effective 20 January 2026, pp. 8, 12, 14. Reviewed 2026-09-09.
Ask for these before ordering
- Approved drawing for the exact model, size and configuration
- Serial-number calibration or factory test record
- Applicable approval certificate and exact scope
- Installation manual and required straight pipe
- Protocol/register map and output power requirements
- Option/accessory codes with included components
- Pressure-loss curve, flange drilling and face-to-face length
- Current written commercial and warranty terms
SPECIFY YOUR REQUIREMENT
Get a quotation for FM35
Tell us the size and quantity you need. Add the fluid, flow or output requirement if known. You can review and send the enquiry from your email app on the next page.
Compare related models
Similar technology does not mean equivalent performance. Compare exact configurations.