# Andeen-Hagerling 2500A 1 kHz Automatic Capacitance Bridge (Standard) (Pre-Owned) # Andeen-Hagerling 2500A 1 kHz Automatic Capacitance Bridge (Standard) (Pre-Owned) ## Key Features At A Glance - Accuracy of 5 ppm (3 ppm with Option E) for capacitance and loss measurements - Stability better than 1 ppm/year (0.5 ppm/year with Option E) - Resolution of 0.5 attofarad (0.0000005 pF) and 0.15 ppm (0.5 aF and 0.07 ppm with Option E) - Temperature coefficient of 0.03 ppm/°C (0.01 ppm/°C with Option E) - Measures low loss to dissipation factor of 1.5x10⁻⁸ tan delta, conductance of 3x10⁻⁷ nS, or resistance up to 1.7x10⁶ gigohms - Full precision measurements in under 0.5 second; repeated measurements in under 40 milliseconds - IEEE-488 and RS-232 interfaces standard for automated test and data logging - External DC bias capability up to ±100 volts with internal switching The Andeen-Hagerling AH 2500A is a 1 kHz automatic capacitance bridge designed to deliver exceptional stability, resolution, and accuracy in both manual and automated capacitance and loss measurements. Operating at a fixed test frequency of 1 kilohertz, the AH 2500A is built around a uniquely designed ratio transformer and a temperature-controlled, fused silica capacitance standard. These elements combine to form a true bridge that provides capacitance results independent of the exact test frequency, with measurement immunity to mechanical shock that makes the instrument suitable for laboratory, factory-floor, and portable field use. The AH 2500A is applied to calibration work including use as a transfer standard in primary and secondary laboratories, fuel gauge calibration, measurement of cryogenic temperatures, thermal expansion measurements for metals and non-metals, radiation measurements using crystalline structures, humidity measurements, thickness measurement of metals and dielectrics, liquid and vapor level measurements, AC resistance measurements to 1000 teraohms, displacement and strain measurements, characterization of insulating media (solid, liquid, or gas) including detection of contaminating water per ASTM D150 and D924, detection of contaminants in refrigerants, monitoring of chemical reactions, research and production testing of capacitance and loss based sensors, and pressure measurements ranging from high vacuum to high pressure. The instrument is specifically suited to applications involving very small changes in capacitance or loss due to its high resolution and stability. ValueTronics offers the Andeen-Hagerling AH 2500A from our 20,000 square foot secure warehouse at 1675 Cambridge Drive in Elgin, Illinois, where every {{CONDITION}} instrument is inspected and verified by our in-house technicians before shipment. Unlike drop-ship resellers and online marketplaces that simply forward listings, we physically hold inventory, perform functional checks, and stand behind every unit we sell — giving precision metrology customers a verified instrument from a known source rather than a description from an unknown seller. ## Brand Heritage Andeen-Hagerling, Inc. was incorporated in 1982 in Solon, Ohio (a suburb of Cleveland) by Carl Andeen and Carl Hagerling. The company traces its technical origins to 1966, when Andeen began Ph.D. research at Case Western Reserve University that required precision ratio-transformer based capacitance measurements. Andeen-Hagerling remains privately owned and continues to manufacture precision capacitance bridges under the same name today, with no acquisitions or rebrands in its history. ## Compare Other Models in This Series The Andeen-Hagerling AH 2500A sits within Andeen-Hagerling's family of precision 1 kHz capacitance bridges, which also includes the AH 2550A and the higher-end AH 2700A. The AH 2500A specifically targets applications requiring 5 ppm accuracy (or 3 ppm with Option E) at a fixed 1 kHz test frequency, with three-terminal BNC connections for medium- and high-impedance unknowns. The bridge is offered in a standard configuration and with the optional Option E precision-enhancement package. Option E improves accuracy from 5 ppm to 3 ppm, stability from 1 ppm/year to 0.5 ppm/year, resolution in ppm from 0.15 to 0.07, and temperature coefficient from 0.03 ppm/°C to 0.01 ppm/°C. All other specifications — range, measurement time, interfaces, packaging, and operating environment — remain identical between standard and Option E configurations. Each pre-owned AH 2500A model listed below is its own dedicated product page with condition-matched pricing and availability. Verify the specific configuration — standard or Option E — that matches your accuracy and stability requirements before ordering. The AH 2500A standard configuration delivers 5 ppm accuracy and 1 ppm/year stability — sufficient for the majority of precision capacitance and loss measurement applications including calibration transfer, dielectric characterization, and sensor-based industrial measurement. For applications requiring the highest available precision at 1 kHz, Option E provides a documented enhancement path with the same physical instrument and interface set. Within the AH 2500A family, the meaningful differentiator is the Option E precision-enhancement package. Option E modifies five specification categories: accuracy (5 ppm → 3 ppm), stability (1 ppm/year → 0.5 ppm/year), ppm resolution (0.15 → 0.07), temperature coefficient (0.03 ppm/°C → 0.01 ppm/°C), and the corresponding non-linearity and absolute resolution expressions. Absolute resolution in attofarads (0.5 aF) is the same for both configurations. All other AH 2500A specifications — range, frequency (1.0000 kHz ±0.005%), measurement time options (40 ms to 20 minutes), test voltage range (0.5 mV to 15 V RMS), DC bias capability (±100 V), IEEE-488 and RS-232 interfaces, packaging (3.5 inches high, 18 lbs), operating temperature (0° to 45°C), and the three-year warranty — are identical across configurations. The comparison table that follows shows the side-by-side specification differences. Model Accuracy Stability Resolution **2500A** 5 ppm 1 ppm/year 0.5 aF (0.15 ppm) Additional differences in specifications beyond the few shown above are not listed here — see each model's full specifications below. ## Accessories Supplied - Hardware for rack mounting - Bail for bench top use ## Product Core & Specifications Specification Value Test Frequency 1.0000 kHz ±0.005% Accuracy (Standard) 5 ppm Stability (Standard) Better than 1 ppm/year Resolution (Standard) 0.5 attofarad (0.0000005 pF) and 0.15 ppm Temperature Coefficient (Standard) 0.03 ppm/°C Minimum Dissipation Factor Measurable 1.5 x 10⁻⁸ tan delta Minimum Conductance Measurable 3 x 10⁻⁷ nanosiemens Maximum Resistance Measurable 1.7 x 10⁶ gigohms Capacitance Range (Parallel C) Negative values to positive values; see datasheet Figure 1 Conductance Range (G) \-6000 nS to +60 000 nS Loss Units Nanosiemens, dissipation factor, series resistance (kΩ), parallel resistance (GΩ), or magnitude of loss vector (jpF) Measurement Time (first measurement) Less than 0.5 second Measurement Time (repeated) Less than 40 milliseconds Measurement Time Formula tb = 0.05 × 2T sec, where T = 0 to 15 Tracking Rate About 25 measurements per second AC Test Signal Voltage Range 0.0005 V to 15.0 V r.m.s. (selectable, ±5%) DC Bias Up to ±100 volts via external DC bias input Sensitivity to Power Line Voltage (Capacitance) ±0.002 ppm per 1% change in line voltage Display Large, variable brightness, 8-digit LED display of capacitance and loss Remote Reporting Digits Up to 9 digits Best Display Resolution (Capacitance) 0.1 aF Best Remote Resolution (Capacitance) 0.01 aF Interfaces IEEE-488 (1978) and RS-232 (both included) Connections Three terminal BNC Standards Oven Warm-up Stable within 15 minutes after power-on Operating Temperature Range 0° to 45°C Storage Temperature Range \-40° to +75°C Humidity 0 to 85% relative humidity, non-condensing Power Requirements 25 watts Power Frequency 48 to 440 Hz Power Voltage Ranges 85 to 115, 102 to 138, 187 to 253, and 204 to 276 volts rms Dimensions (H × D) 3.5 in (8.9 cm) high × 15 in (38.1 cm) deep behind front panel Weight 18 lb (8.2 kg) Safety Designed in accordance with UL1244, IEC348, and BS4743 Radiated Emissions Designed and tested to meet FCC and VDE class A requirements Patents U.S. Patent No. 4,772,844 (foreign patents pending) Warranty Three years (forward and return shipping covered during the first three months) Calibration NIST traceable; internal automatic calibration; calibration against external standards supported **Important:** Per the manufacturer's note: the non-Option-E version of the AH 2500A has been replaced by the AH 2550A bridge. Option E enhancements (3 ppm accuracy, 0.5 ppm/year stability, 0.01 ppm/°C temperature coefficient) are available; consult factory for availability of Option E on bridges not originally purchased with this option.**Important:** The non-Option-E version of the AH 2500A has been replaced by the AH 2550A bridge. Refer to the AH 2550A product page for the current standard model. (Per the manufacturer's datasheet.)**Important:** Option E for bridges that were not originally purchased with this option: consult factory or sales representative for price and availability.**Important:** Cable length correction may be required when measuring at the high end of the capacitance or loss range. The 2500A's CABLE command allows the resistance and inductance per meter of cable pair and the cable length to be entered for automatic correction; uncorrected RG-58-type cables will increase capacitance readings by about 40 ppm per meter of cable pair per µF of capacitance being measured.**Important:** Calibration requires a passcode (changeable only by the instrument manager) to prevent unauthorized calibration. ## About this used unit - Warranty included - Functional verification included - Standard Calibration Upgrade Options: No Calibration Required, NIST Traceable, Z540.1 or ISO 17025 with Data, Z540.3 Guardbanding with Data. - Note that unnecessary accessories may not be included (contact Test Architect to confirm). **Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.** ## Details - **Price:** 0.0 USD - 560.0 USD - **Vendor:** Andeen-Hagerling - **Type:** Cap Bridge - **Tags:** Manufacturers, product_manual_group_1, Product_used, RF, Signal Generators, WaveTek ## Variants | Variant | Price | Available | |---------|-------|-----------| | None | 0.00 USD | In stock | | NIST Traceable | 455.00 USD | In stock | | NIST Traceable with Full Data | 490.00 USD | In stock | | ISO IEC 17025 Accredited | 560.00 USD | In stock | ## Images - Andeen-Hagerling 2500A 1 kHz Automatic Capacitance Bridge (Standard) (Pre-Owned) --- > Source: [ValueTronics](https://valuetronics.com/products/2500a-wavetek-rf-generator-used) > Updated: 2026-05-30