一：概述

NAGKT-I型數字式電氣儀表校驗試驗臺（也叫做：數字式多用表校驗儀、三表校驗儀）是一種LED五位數字式交、直流標準電壓、電流發生器，用于校驗數字式電表、各種指針式電表及直流0.2級，交流0.5級以下各類表頭。本儀器電壓輸出五檔（0~1000V）；電流輸出六檔（0~10A）；可以選配：中值電阻2×11檔(0Ω~24MΩ)；交流頻率50Hz,60Hz,400Hz（數字合成，按鍵選擇）。以上項目及量程變換均通過內部開關轉換。采用**的16位A/D轉換芯片，轉換速度和精度得到了大幅度提高；AC/DC采用真有效值轉換芯片，保證了交流輸出的精度；整機線性度好。采用了新型的復合大功率放大器，輸出功率強大，可靠性高，失真度小。輸出調節采用進口電位器，壽命長，調節細度高。整機采用“閉環控制”，輸出穩定度高。電壓短路、電流開路自動保護，完全符合新三表鑒定規程。

二、工作原理：

本儀器有數字合成正弦波發生器單元、功放單元、電源及保護單元、量程單元、A/D單元、顯示單元、鍵盤單元及標準電阻器等組成。

三、技術性能：

2.1性能參數：

2.2：交流失真度：不大于1%。

2.3：直流紋波系數：不大于0.5%；電流10A不大于3%。

2.4：穩定性：儀器預熱一小時后，1分鐘內輸出漂移應小于基本量程滿度的±0.05%，作精密測量時需預熱2小時。

2.5：外型尺寸：480×340×134（mm）。

2.6：重量：10Kg。

NACKT-I electrical instrument test-bed

I. Overview

NAGKT-I digital electrical instrument calibration test bench (also called:digitalmultimetercalibrator,three-tablecalibrator) is a five-digit LED AC, DC standard voltage, current generator for Calibration digital meters, a variety of hands-meter and DC 0.2, the exchange of0.5below thevarious typesof table head.(0 ~ 12MΩ); AC frequency of 50Hz, 60Hz, 400Hz (digital synthesis, the output voltage of the three-phase voltage range of 0 ~ Button toselect). Theabove itemsand range conversion areconverted byinternal switches. Using the latest 16-bit A / D converter chip, conversion speed and accuracy has been greatly improved; AC / DCconverter with trueRMS value toensure the accuracy ofACoutput;整機linearity is good. Using a new type of composite high-power amplifier, the output power of strong, highreliability, lowdistortion. Output adjustment using importedpotentiometer, longlife,high fineness regulation. The machine adopts "closed-loop control", the output stability is high. Voltageshort-circuit, opencurrent automatic protection, in full compliancewith the new threetableidentification procedures.

Second, the working principle:

The instrument has a digital synthesis sine wave generator unit, power amplifier unit,powerand protectionunit,rangeunit, A / D unit, display unit, keyboard unit and standard resistors and other components.

Third, the technical performance:

2.1 Performance parameters:

2.2: AC distortion: less than 1%.

2.3: DC ripple factor: not more than 0.5%; current 10A not more than 3%.

2.4: Stability: the instrument warm-up after one hour, 1 minute output drift should belessthan the full rangeofthebasic range of ±0.05%, for precision measurements need to warm up 2 hours.

2.5: Overall dimensions: 480×340×134(mm).

2.6: Weight: 10Kg.