ABB 7ML5202-0EA0 | SITRANS LR260 Radar Level Transmitter | 80m Range | In Stock

Description

Key Technical Specifications

• Measurement Principle: FMCW (Frequency Modulated Continuous Wave) Radar.
• Frequency: 26 GHz (K-band).
• Measuring Range: 0.3 m to 80 m (depending on process conditions).
• Accuracy: ±3 mm (standard conditions).
• Output Signal: 4-20 mA with superimposed HART protocol (two-wire).
• Antenna Material: PTFE (Teflon) – Corrosion and buildup resistant.
• Antenna Type: Horn antenna (DN80/DN100 flange compatible).
• Process Temperature: -40°C to +80°C (-40°F to +176°F).
• Process Pressure: -0.1 to +4 bar (vacuum to low pressure).
• Protection Rating: IP66 / IP67 / NEMA 4X.
• Housing Material: Aluminum alloy (coated) or Stainless Steel (optional).
• Display/Interface: Optional local display with 4-button keypad; Configurable via handheld communicator or PC.

Product Introduction

Dust kills ultrasonic sensors. I’ve watched $2,000 ultrasonic units go blind in a cement silo because a little puff of powder coated the transducer. The ABB 7ML5202-0EA0 (SITRANS LR260) is the fix for that headache. It uses 26 GHz radar, which cuts through dust clouds, steam, and changing temperatures like they aren’t even there. It’s a “set it and forget it” device. You bolt it to the flange, wire it up, and it gives you a steady level reading even when the tank is being filled at full speed and the air is thick with particulate.The real value here is the PTFE antenna. In corrosive chemical tanks or sticky grain silos, gunk builds up on everything. PTFE sheds most materials, so the signal doesn’t get blocked by a layer of sludge. I’ve used these on lime silos where the dust was so bad you couldn’t see your hand in front of your face, and the LR260 held a stable 4-20mA signal while the ultrasonics next door were flashing fault codes. Just don’t try to use this in a high-pressure reactor; it’s rated for near-atmospheric conditions only. If you need high pressure, you’re looking at the wrong tool.

Quality SOP & Tech Pitfalls (The Reality Check)

The Lab Report (SOP)
We treat every radar unit like it’s going into a critical loop, because it probably is.

1. Visual Inspection: We check the PTFE antenna surface for scratches or shipping damage. Even a deep gouge can scatter the radar beam. We verify the flange face is flat.
2. Bench Simulation: We connect the unit to a 24V DC loop with a HART communicator. We simulate a target at 5m, 20m, and 50m using a reflection plate in our test bay to ensure the echo processing logic is working.
3. Signal Stability Test: We run the output at 50% (12mA) for 2 hours while vibrating the test stand. The signal must not drift more than ±0.1%.
4. Leak Check: We pressurize the housing slightly and spray soapy water on the conduit entries and display cover to ensure no moisture ingress points exist.
5. Packaging: The antenna tip is capped with a protective plastic cover. The unit is boxed with custom foam inserts to prevent the heavy electronics head from snapping the antenna during transit.

The Engineer’s Warning (Pitfalls)

• Mounting Position is Critical: Do not mount this directly over the fill chute. I don’t care how good the radar is; if you aim it at a stream of falling grain or sand, you will measure the stream, not the pile. Offset the mounting by at least 1/3 of the tank radius. Also, avoid mounting near internal ladders or baffles; the radar sees them as false targets.
• Condensation in Cold Climates: In freezing environments, moisture can condense inside the housing or on the antenna if the process temperature swings wildly. While the PTFE sheds water, ice buildup can attenuate the signal. If you are in a sub-zero zone, ensure the housing heater option (if available) is powered, or install a sun-shield to reduce thermal shock. I once saw a unit fail because the cover gasket wasn’t seated, froze solid, and cracked the display window.

Installation & Configuration Guide

Time estimate: 45 minutes (including basic config).

1. Pre-Installation Safety ⚠️
   • Isolate the tank. Ensure no pressure or hazardous material is present during drilling/flange welding.
   • Verify the flange size matches the order (usually DN80 or DN100 for this model).
   • Clean the tank nozzle. Remove any burrs or weld spatter that protrude into the tank; they create false echoes.
2. Mechanical Mounting
   • Apply high-temp anti-seize compound to the flange bolts.
   • Insert the gasket (PTFE or graphite recommended).
   • Bolt the unit down evenly. Do not overtighten; you can warp the flange and misalign the antenna. Torque to spec (usually ~40-50 Nm depending on bolt size).
   • Ensure the antenna points straight down. Use a level on the housing top.
3. Electrical Wiring
   • Run shielded twisted pair cable (18 AWG min).
   • Connect 24V DC to the terminals. Polarity usually doesn’t matter for the power input, but check the label.
   • Grounding: Connect the cable shield to the ground terminal inside the housing AND ground the other end at the control panel. This is non-negotiable for noise immunity.
4. Commissioning & Setup
   • Power up. The LED should flash green.
   • Connect your HART communicator (e.g., Trex or Field Communicator).
   • Quick Setup Wizard: Enter the tank height (Empty Calibration) and the distance to the bottom (Full Calibration).
   • False Echo Suppression: Run the “Auto-Learn” function. The device will map out the ladder, nozzle, and walls, then ignore them. Crucial Step.
   • Verify the 4mA (empty) and 20mA (full) output against known references.

Compatible Replacement Models

Frequently Asked Questions (FAQ)

Q: Will this work on a tank with heavy foam on the surface?
A: It depends on the foam density. Dry, light foam is transparent to 26 GHz radar, so it measures the liquid level underneath fine. Thick, wet foam can absorb the signal and reflect off the foam surface. If you have heavy wet foam, you might need a guided wave radar (GWR) instead. Test it if possible.Q: Can I use this for hydrofluoric acid or strong solvents?
A: The PTFE antenna is highly resistant to almost all chemicals, including HF and strong acids. However, check the housing material. The standard aluminum housing might not survive a leak or heavy fumes. For aggressive chemical service, specify the stainless steel housing option.Q: The reading is jumping around wildly. What’s wrong?
A: 90% of the time, it’s a false echo. You probably mounted it too close to a wall, ladder, or the fill stream. Go into the menu and run the “False Echo Suppression” or “Mapping” routine again. If that fails, check your grounding. A floating ground can introduce 60Hz noise that looks like level jumps.Q: Does this require a separate power supply for the display?
A: No. It’s a two-wire loop-powered device. The 24V DC powers the electronics, the radar, and the display (if installed). Just make sure your power supply can handle the total current load of all devices on the loop.Q: How do I update the firmware?
A: You can’t easily do it in the field without specific software (SITRANS Explorer) and a modem interface. Honestly? Don’t bother unless ABB support tells you there’s a critical bug. These units are stable as-is. If it’s working, leave it alone. Messing with firmware in a live plant is how you create downtime.