PIE 525Plus Thermocouple RTD & Milliamp Calibrator

Three calibrators in one handheld — thermocouple, RTD, and full-function milliamp — with patented Ground Leak Detection (US Patent 7,248,058), NIST-traceable cold junction ±0.05 °C, and AMS 2750 Field Test Instrument capability when certified by an accredited laboratory.

Key advantages

3-in-1 — Source/read 14 thermocouple types + 12 RTD types, plus full mA loop calibrate (source, read, 2-wire simulate, power & measure).
Ground Leak Detection — Patented loop diagnostics find ground fault / current leakage before product or safety events.
Lab-grade CJC — Cold junction ±0.05 °C (±0.09 °F), NIST-traceable thermistor bonded to isothermal mass.
Smart-transmitter RTD lock — Handles pulsed excitation on PLC / DCS / multivariable transmitter RTD inputs; ConnectSense shows 2/3/4-wire status.
AMS 2750 ready — Capable as Field Test Instrument for heat-treat SAT/TUS work when certified by an accredited lab.

Typical applications

Thermocouple and RTD transmitter, PLC, and recorder calibration.
4–20 mA loop checkout with power & measure and HART 250 Ω resistor built in.
Finding zero-shift from moisture/corrosion ground leaks after weather events.
Aerospace heat-treat Field Test Instrument work under AMS 2750 (when lab-certified).
Replacing high-resistance thermocouple probes before burnout (OPEN TC + ohms).

Selection guide

525Plus vs 525B — Choose 525Plus when you also need milliamp source/read/simulate and Ground Leak Detection; 525B is TC/RTD/Ω/mV only.
Sensor set — Confirm TC types (J K T E R S B N G C D L U P) and RTD curves (Pt 10…1000 Ω α=3850; Pt100 3902/3916/3926; Cu10/50; Ni120).
Package — Standard vs Basic accessory package; optional magnet strap (020-0236) and T/C wire kits (020-0202 / 020-0203).
Power — Four AA alkaline included; optional Ni-MH kit 020-0103.

Common mistakes

Ordering 525B when the job needs mA loop power/measure or Ground Leak Detection — that is 525Plus.
Ignoring cold-junction uncertainty on TC work (±0.05 °C CJC still must be budgeted in the uncertainty stack).
Using 2-wire RTD without lead-resistance allowance when 3/4-wire is available.
Assuming AMS 2750 Field Test Instrument status without accredited certification of the unit.

When to RFQ / what to tell us

Confirm 525Plus (not 525B); accessory package Standard or Basic.
TC/RTD types on site; need for magnet strap / T/C wire kits / Ni-MH kit.
Quantity and ship-to country.

Request a Quote · Get selection help

Specs

Spec	Value
SKU	44924
Brand	PIE (Practical Instrument Electronics)
Model	525Plus
Product type	Diagnostic thermocouple, RTD & milliamp calibrator
Thermocouple types	J K T E R S B N G C D L (J-DIN) U (T-DIN) P (Platinel); −13.000 to 80.000 mV
RTD types	Pt 10/50/100/200/500/1000 Ω (α=3850); Pt100 3902/3916/3926; Cu10/50; Ni120; 0–401 / 0–4010 Ω ranges
TC accuracy	±(0.008% of reading + 0.006 mV); CJC ±0.05 °C (±0.09 °F) NIST-traceable
RTD accuracy (3/4-wire)	±(0.015% of reading + 0.05 Ω) from 1–10.2 mA excitation
mA range / accuracy	0.000–24.000 mA; ≤ ±(0.02% of reading + 0.003 mA)
Loop drive	≥24 VDC @ 20 mA; 1200 Ω at 20 mA (950 Ω with HART resistor or leak detection)
Diagnostics	Ground Leak Detection (US Patent 7,248,058); OPEN TC resistance threshold ~18 kΩ
Auto step	2/3/5/11/21 steps; 5–60 s step times
Operating temperature	−25 to 60 °C (−10 to 140 °F)
Size / weight	5.63 × 3.00 × 1.60 in (143 × 76 × 41 mm); 12.1 oz / 0.34 kg with boot & batteries
Batteries	Four AA alkaline; ~25 h TC/RTD, ~8 h milliamp typical

Documents

FAQ

Q: How is 525Plus different from 525B? A: 525Plus adds full milliamp calibrator functions (source/read/simulate/power & measure), built-in 250 Ω HART resistor, and patented Ground Leak Detection. 525B is TC/RTD/Ω/mV only.

Q: Does it support pulsed RTD excitation? A: Yes — OEM states unique circuitry for smart/multivariable transmitters, PLC inputs, and multichannel recorders with pulsed excitation.

Q: What should I send for a quote? A: Confirm 525Plus, accessory package, any wire kits/magnet strap, quantity, ship-to.