Phone: 253-927-6186

F700 Thermometry Bridge Standard.
The Model F700 Thermometry Bridge Standard is a high accuracy resistance bridge designed specifically for resistance thermometry. Its unique AC bridge circuitry eliminates thermal EMF effects to provide you with fast, reliable measurements under a wide range of real operating conditions.
F700 Thermometry Bridge a special input guard circuit maintains accuracy by minimizing the effect of probe or cable leakage to ground.

Thermometry Bridge Standard

Model  Description 
F700  Model F700 Thermometry Bridge Standard

The effect of cable and probe reactance is eliminated by an on-board quadrature servo allowing you typically to make measurements up to 100 meters from the PRT.

The differential capability allows the resistance of one PRT to be measured against another directly and provides the most accurate comparison calibration technique.

The F700 can be used with one or more switchboxes for multi channel calibration.

F700 Thermometry Bridge Standard Specification
Accuracy F700A: <±1ppm of reading or 1 digit, whichever is the greater.
Equivalent to 0.25mK @ unity ratio (0.01°C) or 1mK
over the full range

F700B: <±0.5ppm of reading or 1 digit, whichever is the greater.
Equivalent to 0.25mK @ unity ratio (0.01°C) or 0.5mK
over the full range

  Temperature equivalents for 25.5ohm SPRT against
a 25ohm standard @ 1mA

F700A: <±5ppm @ unity ratio, equivalent to 6mK up to 1064°C

F700B: <±2.5ppm @ unity ratio, equivalent to 3mK up to 1064°C

Temperature equivalents for 0.25ohm HTSPRT against a 1ohm standard @ 10mA
Resolution 1 least significant digit
Linearity <±1 least significant digit
Measurement time 10 second for full balance
Warm up time <30 seconds with external standard, <5 minutes with internal

Thermometers R0.01 of 1000ohm, 100ohm,25ohm, 10ohm, 1ohm, 0.25ohm
and any intermediate value

External standard resistor range 1ohm to 1000ohm AC/DC resistance
Internal Standard Resistor 100 ohm ±50ppm, with t/c of <0.3ppm/°C, in a temperature
controlled oven at 36°C. A trim control allows calibration
against an external standard.

Measurement Range 0-3.999999 ratio of two resistors; 0-3.999999 ohms where Rs = 1 ohm
0-399.9999 ohms where Rs = 100 ohms; 0-1500.000 ohms
where Rs = 1000 ohms.

Sensor current 0.1, 0.2, 0.5, 1 ,2, 5, or 10mA plus root2 multiplier.
Constant current, stabilized to ±1% of nominal value.

Communications RS232 300 baud, 8 bits, no parity and 2 stop bits
IEEE-488 Address selectable from 0 to 15
Analogue outputs ±10V null balance signal, unfiltered P.S.D output
±10V null balance signal, filtered output (1 Hz bandwidth)
Operating conditions 0°C to 30°C (32°F to 86°F), 10 to 90%RH
Power requirements 240,220,120,100 VAC (±10%) selectable on rear panel,
50 or 60 Hz, 70VA max.

Dimensions / weight 520mm (W) x 155mm (H) x 466mm (D). 3U x 19" front panel. 15Kg

We accept

  • American Express
  • Master Card
  • VISA
  • Purchase Orders


  • Hotek Technologies, Inc
  • tel: 253-927-6186