The HART supply isolation amplifier AD-STH 40 GVC is designed for the galvanic isolation and amplification of transmitter signals (0/4-20 mA) and standard analog signals (0/4-20 mA and 0/2-10VDC). When connecting a 2 - wire transmitter, it is powered directly through an electrically isolated and current limited power supply voltage. Because the AD-STH 40 GVC is permeable on the current path for FSK signals (Frequency Shift Keying, eg HART-protocol) also a smart HART-transmitter can be connected at the input of the supply isolation amplifier. This HART transmitter can be programmed or read out from the output of the AD-STH 40 GVC using the integrated programming resistor. The standard signals 0/4-20 mA and 0/2-10 V are freely selectable via switch or terminal on both the input and at the output. All ranges are calibrated fixed, but can be adjusted via front-trimmer. In addition, this device comes standard with a configuration interface AD-PC, with which the input and output measurement signal with the optional AD-Studio programming software in the range of max. 20 mA or 10 VDC can be freely programmed. The selected linear output signal follows the input size up to a limit independent of the connected load. Input, output and power supply voltage are galvanically isolated from each other with high insulation. An integral electronic wide range power supply with high efficiency prevents strong heating and allows high output loads.



Galvanically isolated supply of a smart HART-transmitter while separation, amplification or conversion of standard analog signals.

Specific characteristics

  • All standard signals at the input and output are freely selectable
  • FSK transmission (e.g. HART protocol)
  • Switchable zero and span trimmer
  • Special signals can be parameterized via interface

Business data

Order number
Customs tariff number / country of origin 8543 70 90 / Deutschland


Technical specifications

Input current
Measuring range 0 ... 20 mA; 4 ... 20 mA 1)
Input resistance Ca. 75 Ohm
Resolution 10 Bit
Input voltage
Measuring range 0 ... 10 V; 2 ... 10 V 1)
Input resistance >700 kOhm
Resolution 10 Bit
Transmitter supply
Full load voltage Ca. 20 V DC
Current limit Ca. 30 mA
Open-circuit voltage Ca. 26 V DC
Input filter
Setting range (via interface) 10 ms / filter value (0 ... 30000)
Output current
Output range 0 ... 20 mA; 4 ... 20 mA 1)
Max. burden 400 Ohm
Residual ripple 50 µAss
Resolution 11 Bit
Output voltage
Output range 0 ... 10 V; 2 ... 10 V 1)
Min. burden 10 kOhm
Residual ripple 20 mVss
Resolution 11 Bit
Voltage range AC 50 ... 253 V AC, 50/60 Hz
Nominal voltage AC 230 V AC
Voltage range DC 20 ... 253 V DC
Nominal voltage DC 24 V DC
Power consumption AC / DC 3,9 VA / 1,9 W
Trim range Ca. +/- 20 %
Transmission behaviour
Basic accuracy < 0,3 %
Temperature influence 100 ppm/K
Response time ~ 70 ms
Dimensions (WxHxD) 18x110x134 mm
Type of protection IP 20
Connection method Detachable terminal clamp
Terminals, wire cross section 2,5 mm² flex wire / 4 mm² one wire
Bolting torque terminals 0,5 Nm
Weight ~ 130 g
Manner of fastening 35 mm DIN rail 35mm
Environmental conditions
Ambient temperature -10 ... 50 °C
Storage and transport -10 ... 70 °C (no condensation)
Product family standard EN 61326-1 2)
Emitted interference EN 55011, CISPR11 Cl. B, Gr. 1
Electrical safety requirements
Product family standard EN 61010-1
Overvoltage category II
Pollution degree 2
Galvanic isolation, test voltages
Input / output 2,5 kV (1 min.)
Signal / supply unit 3 kV (1 min.)
Protection circuits
Input Electrical surge protection
Output Electrical surge protection
Power supply Protection against overvoltage, overcurrent and reverse polarity
1) Special signals are configurable via the interface.
2) During electromagnetic disturbance minor changes in output signal are possible.

Block and wiring diagram




CAD / CAE Daten

CAD model is not yet available for this product.

The CAD product overview can be found at:

Cookie settings
made with ♡ by