NE Test System

Test System for Neutral Electrodes and Cord Tests   
- NE cord attachment test
- NE contact impedance test
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The Complete Neutral Electrodes (NE) Test System consists of the following components:
  1. High Frequency Power Amplifier – WhaleTeq HFPA150
  2. DC Power Supply – Tektronix PWS2323 (Rigol DP116A or equivalent*)
  3. Oscilloscope – Tektronix DPO2002B (Rigol DS1074B or equivalent*)
  4. Digital Multimeter - Fluke 87V (Brymen BM-829 or equivalent*)

* Please contact our sales representative ( for other available equivalents to suit your specific needs. 
A Neutral Electrode shall be provided for monopolar electrode HF surgical equipment with a rated output in excess of 50 W. According to IEC 60601-2-2: 2009, the below listed clauses are required for NE compliance. Our WhaleTeq Neutral Electrodes (NE) Test System is the solution for your product to fulfill the requirements:


For the Cord Insulation and Contact Impedance testing, special and hard to find electrical equipment are required to fulfill the required tests. Understanding the needs of manufacturers, WhaleTeq designed a NE Impedance tester – HFPA150 to meet the requirement of contact impedance testing. The following is an overview of the WhaleTeq Test Solutions:

1. NE Cord Attachment Test

Figure 1 illustrates the setup of the NE Cord Attachment Test which consists of a DC power supply to generate the required current IDC and a DMM to measure the value of current, altogether to calculate the impedance of the cord attachment.
Alternately, if a DC power supply used has a voltage and current display function, such as the  Tektronix PWS4000 series, which can display output voltage and current simultaneously when connected to the test load. In such case, a DMM is not required. 

                                   Figure 1.  NE Cord Attachment Test setup

2. NE Ccontact Impedance Test
According to IEC 60601-2-2: 2009, NE (Neutral Electrode) contact impedance.

“The impedance of the electrical contact between the surface of the NE application site and the NE cord connection shall be low enough to prevent a risk of patient burn due to ohmic heating during passage of HF surgical current.”

As described in the standard clause:
    - For conductive NE, contact impedance shall not exceed 50 Ω,
    - For capacitive NE, capacitance shall be no less 4 nF over the frequency range of 200 kHz – 5 MHz
    - Tested with a current of approximately 200 mA and frequency of 200 kHz – 5 MHz
    - The NE under test is placed in full and firm contact on a flat metallic plate.
Based on these requirements, Figure 2 illustrates the test setup in order to fulfill 200 mA r.m.s. and 50Ω impedance, the HF sine wave generator must offer 10 Vrms (~28 Vp-p) output voltage. Most FG (Function Generator) currently on the market cannot meet this output specification, and an external HF power amplifier is therefore required to fulfill the full range NE contact impedance testing requirements.
The NE Contact Impedance Test setup includes a Function Generator capable of generating 10 kHz to 10 MHz, less than 10Vp-p sine wave, a NE impedance tester HFPA150 and an oscilloscope with voltage probes.

                                         Figure 2. NE Contact Impedance Test setup