Hydac HDA 4870-A-3000-424 Steelworks Transmitter, 3000 psi

A cable-connected pressure transmitter made for steelworks conditions

The Hydac HDA 4870-A-3000-424(PSI)10m (HYDAC part number 925711) is a variant of the HDA 4800 transmitter, built for iron and steelworks where water, humidity, heat and vibration punish ordinary sensors. The cell is a thin-film strain gauge on a stainless steel membrane, and the body is encapsulated with a cable outlet with strain relief and shrink sleeving. It measures 0 to 3000 psi, outputs 4 to 20 mA on two conductors, and comes with 10 metres of Teflon cable.

High accuracy is a feature of the series: 0.125 percent of full scale typical to DIN 16086, with a very low temperature drift.

Technical specifications

Understanding the code

HDA 4 8 7 0 – A – 3000 – 424 (PSI) 10m: the 7 selects the 9/16-18 UNF (SAE-6) male connection, 0 the open-ended cable, A the 4 to 20 mA signal, 3000 the range in psi, 424 the modification for iron and steel works and 10m the cable length. The datasheet allows cable lengths of 6, 10, 15, 20, 25 or 30 metres and a 0 to 20 mA, three-conductor signal with code E. This is the SAE (psi) variant; for metric ranges and G1/4 ports the datasheet refers to the European catalogue, where the HDA 4840 appears.

Why the steelworks version

The extra encapsulation protects against water, humidity and vibration, which is why the series uses a cable outlet instead of a plug that could collect moisture. Wire it as a two-conductor loop with brown as signal plus and blue as signal minus, and keep the screened cable away from heavy power lines. At 3000 psi it covers typical hydraulic pressures in rolling mills and casting equipment. Check the permitted load resistance, (supply minus 10 V) divided by 20 mA, against your controller input.

Tighten the connection to 20 N·m with the recommended sealing, and avoid pulling on the cable at the strain relief. Because the sensor is intended for harsh conditions, record the install date and plan a periodic calibration check, since the annual drift figure of 0.1 percent of full scale will add up over several years.

Plan the cable route before installation: the 10 metre lead is a fixed length, so allow for bends and for any junction box between the transmitter and the controller. The sensor tolerates vibration up to 25 g, which suits mounting directly on heavy plant, and the shrink sleeve and strain relief should not be cut or removed during installation.

Documents and quotation

The HDA 4800 datasheet for iron and steelworks is attached. Please give the full code including range and cable length. See also our pressure instrumentation range.

How the HDA 4870-A-3000-424(PSI)10m works

The HDA 4800 steelworks series measures relative pressure with a thin-film strain gauge deposited on a stainless steel membrane. System pressure reaches the membrane through an orifice in the pressure port, which damps pressure peaks. As the membrane deflects, the resistance of the strain gauge bridge changes, and the built-in electronics convert this into a 4 to 20 mA current loop signal. Reverse polarity protection of the supply, overvoltage, override and short-circuit protection are provided, according to HYDAC.

What makes the HDA 4870-A-3000-424(PSI)10m different from a standard industrial transmitter is the 424 steelworks modification: the device is encapsulated, the cable outlet has strain relief and a heat shrink sleeve protects the sensor against bending. HYDAC states that this gives additional protection against water, humidity and vibration, and that the EMC characteristics keep the signal stable under heavy high-frequency interference.

HDA 4800 steelworks series data from the datasheet

Selection & ordering guide

• Mechanical connection: the metric brochure lists G1/4 A and G1/2 A ISO 1179-2 (codes 4 and 2). Code 7 on this model is the SAE-6 (9/16–18 UNF) port of the psi version.
• Electrical connection: 0 = jacketed cable, 6 = M12x1 4-pole plug (IP 67 with mating connector).
• Output: A = 4 – 20 mA, 2-conductor; E = 0 – 20 mA, 3-conductor source.
• Range: select the range so that normal working pressure sits well below full scale and pressure peaks stay below the overload rating.
• Cable length: 6, 10, 15, 20, 25 or 30 m, only with cable connection 0.

Our team can help confirm the correct ordering code for the HDA 4870-A-3000-424(PSI)10m or a metric equivalent from the HDA 4800 steelworks series.

Installation & maintenance

• Wire the 2-conductor loop with brown to signal + and blue to signal –; the black lead is not connected in output A.
• Connect the cable shield as required by your plant earthing scheme and route the cable away from high-current conductors.
• Do not cut or remove the shrink sleeve or the strain relief, since they are part of the moisture and vibration protection.
• Check the loop load against R_Lmax = (U_B – 10 V) / 20 mA.
• Plan periodic calibration checks; with a long-term drift of ±0.1 % FS per year, the error adds up over several years.

Typical applications in Oman & the GCC

HYDAC developed the series specifically for steelworks and rolling mill applications. In Oman and the GCC the HDA 4870-A-3000-424(PSI)10m suits hydraulic systems in steel plants, rolling mills, continuous casting machines and heavy presses, as well as other plants where water spray, humidity and vibration make a plug-type transmitter unreliable.

Why source the HDA 4870-A-3000-424(PSI)10m from Seven Star LLC

Seven Star LLC supplies HYDAC pressure transmitters and sensors across Oman and the GCC. Send us the full model code, pressure range, port and cable length to request a quote, and our team can help confirm the correct ordering code.