Universal I/F Converter – PR Electronics 4222


  • Input for RTD, TC, Ohm, potentiometer, mA and V
  • Frequency output NPN, PNP and TTL
  • Generates frequencies from 0.001…25000 Hz
  • 2-wire supply > 16 V
  • Universal AC or DC supply

Advanced features

  • Programmable via detachable display front (4501), process calibration, signal simulation, password protection, error diagnostics and selection of help text in several languages.


  • Linearized, electronic temperature measurement with RTD or TC sensor.
  • Conversion of linear resistance variation to a frequency signal, e.g. from solenoids and butterfly valves or linear movements with attached potentiometer.
  • Power supply and signal isolator for 2-wire transmitters.
  • Process control by way of a frequency signal transmitted to e.g. a PLC or a process computer.
  • Galvanic separation and conversion of analog signals to frequency signals.

Technical characteristics

  • When 4222 is used in combination with the 4501 display / programming front, all operational parameters can be modified to suit any application. As the 4222 is designed with electronic hardware switches, it is not necessary to open the device for setting of DIP switches.
  • A green front LED indicates normal operation.
  • Continuous check of vital stored data for safety reasons.
  • 3-port 2.3 kVAC galvanic isolation.


Operating temperature -20°C to +60°C
Calibration temperature 20…28°C
Relative humidity < 95% RH (non-cond.)
Protection degree IP20
Dimensions (HxWxD) 109 x 23.5 x 104 mm
Dimensions (HxWxD) w/ 4501/451x 109 x 23.5 x 116 / 131 mm
Weight approx. 155 g
Weight incl. 4501 / 451x (approx.) 170 g / 185 g
Wire size 0.13…2.08 mm2 AWG 26…14 stranded wire
Screw terminal torque 0.5 Nm
Supply voltage, universal 21.6…253 VAC, 50…60 Hz or 19.2…300 VDC
Fuse 400 mA SB / 250 VAC
Max. required power ≤ 2.5 W
Max. power dissipation ≤ 2.5 W
Isolation voltage
Isolation voltage, test / working 2.3 kVAC / 250 VAC
Response time
Temperature input, programmable (0…90%, 100…10%) 1…60 s
mA / V input (programmable) 0.4…60 s
Auxiliary supplies
2-w. supply (term. 44…43) 25…16 VDC / 0…20 mA
Programming PR 45xx
Signal / noise ratio Min. 60 dB (0…100 kHz)
Accuracy Better than 0.1% of sel. range
EMC immunity influence < ±0.5% of span
Extended EMC immunity: NAMUR NE21, A criterion, burst < ±1% of span
RTD input
RTD type Pt100, Ni100, lin. R
Cable resistance per wire 50 Ω (max.)
Sensor current Nom. 0.2 mA
Sensor error detection Yes
Short circuit detection < 15 Ω
TC input
Thermocouple type B, E, J, K, L, N, R, S, T, U, W3, W5, LR
CJC via int. mounted sensor < ±1.0°C
Sensor error detection Yes
Sensor error current: When detecting / else Nom. 2 μA / 0 μA
Current input
Measurement range 0…23 mA
Programmable measurement ranges 0…20 and 4…20 mA
Input resistance Nom. 20 Ω + PTC 50 Ω
Voltage input
Measurement range 0…12 VDC
Programmable measurement ranges 0/0.2…1, 0/0.5…2.5, 0/1…5, 0/2…10 VDC
Input resistance Nom. 10 MΩ
Frequency output range 0…25000 Hz
Min. frequency (span) 0.001 Hz
Other output types PNP, NPN and TTL
Sensor error indication, programmable 0…26250 Hz
of span = of the currently selected measurement range
EMC 2014/30/EU
LVD 2014/35/EU
RoHS 2011/65/EU
EAC TR-CU 020/2011
EAC LVD TR-CU 004/2011
c UL us, UL 508 / C22.2 No. 14 E231911
FM 3025177


PR Electronic 4222 Universal I-f converter-DpstarGroup