LEAK CURRENT HiTESTER ST5540

Leak Current Measurement, an Essential Part of Electrical Safety (for medical-use electrical devices)

To ensure the safe use of electrical products, electrical safety tests such as insulation resistance, withstand voltage, ground resistance, and leakage current must always be conducted. Hioki Leakage Current Testers comply with laws and standards regarding medical electrical equipment as well as non-medical electrical equipment, and can be used to measure leakage current in all types of electrical products from computers to medical equipment.
The ST5540 consists of measurement networks that simulate the human body and a high-frequency volt meter, and is also capable of switching power supply polarities and making measurements under simulated single fault conditions in equipment under test.

Key Features

  • Compliance with IEC 60601-1:2005 Ed 3.0, JIS T 0601-1:2012 for medical-use electrical devices and essential to electrical safety (*1)
  • Compliance with Electrical Appliances and Materials Safety Act, JIS, IEC, and UL standards for general-use electrical devices
  • Uninterrupted polarity switching function dramatically reduces cycle time
  • Support for rated currents up to 20 A gives the instrument more than adequate capability for testing products designed to comply with new standards
  • Communications functionality and external I/O support allow automatic testing on production lines
  • *1:Starting on June 1, 2012, medical electrical equipment sold in the EU must comply). Model ST5540 comply with IEC 60601-1:2005+ A1:2012 (Ed 3.1), and IEC 62353 of 2017.

Model No. (Order Code)

ST5540 For medical-use and electrical devices
Note: The photograph portrays the Japanese version of the product. Other countries’ versions of the product lack the outlet on the front panel.
Note: Always use an isolation transformer when measuring leak current for medical-use electrical devices. The ST5540 does not include an isolation transformer. When measuring medical-use electrical devices, use a step-up isolation transformer or similar component operating at 110% of the rated supply voltage as the power supply for the device under test.

Leak Current Measurement - Essential to Electrical Safety

Compliance with IEC 60601-1:2005 (3rd Edition) is now mandatory.
The ST5540 also complies with JIS T0601-1:2012.

The ST5540 series features an improved measuring method and dramatically faster cycle times thanks to its uninterrupted polarity switching capability. The new devices support rated currents of up to 20A, making it more than ideal for use with products built to new standards.

Leak Current Testing of Medical Electrical Devices

In order to prevent the danger of electric shock, electrical devices use power supplies that are isolated from parts of the device that may come into contact with the body. However, it is impossible to achieve infinite insulation resistance. Some leak current always exists, and its magnitude changes as the insulation degrades over time. The LEAK CURRENT HiTESTER ST5540/ST5541 provides an easy-to-operate solution for measuring leak current in electrical devices, making it eminently suitable for use in an extensive array of applications, ranging from production lines to equipment maintenance and inspections.

Combine with Model 3157 to meet JIS T 1022:2006: Safety requirements of electrical installations for medically used rooms in hospitals and clinics

Combine the ST5540 with Hioki Model 3157 AC Grounding HiTester for Leak Current and Safety Conductor Testing

The following are key parts of any safety inspection of electrical equipment:
•Leak current test: Measure with the ST5540 and ST5541.
•Safety conductor test (also known as a ground line resistance test or ground conductor test): Measure with the 3157.
The 3157 can also be used for conducting measurements under the JIS T 1022:2006 safety standard for hospital electrical equipment.

3157 AC Grounding HiTester

Basic specifications

Accuracy guaranteed: 1 year
Measurement methods Measurement of voltage drop across body simulated resistance points, Calculation and display of current values, True rms measurement, Measurement unit floats relative to instrument ground.
Measurement modes Leak current measurement, voltage measurement, safety conductor current measurement
Standards compliance
(NW: Body simulated resistance)
[NW-A] • Electrical Appliances and Materials Safety Act
[NW-B1] • Medical electrical equipment: IEC 60601-1:1988+ A1:1993+ A2:1995, JIS T 0601-1:1999
[NW-B2] • Medical electrical equipment: IEC 60601-1:2005+ A1:2012, JIS T 0601-1:2012 and complement 1:2014, IEC 62353
[NW-C]
• Measurement of touch current and protective conductor current: IEC 60990:2016
• Electrical equipment for measurement, control, and laboratory use: IEC 61010-1:2010+ A1:2016
• Information technology equipment: IEC60950-1:2005+ A1:2009+ A2:2013
• Audio, video and similar electronic apparatus: IEC 60065:2014
• Personnel Protection Systems for EV: UL 2231-1:2012 (Amended 2016), UL-2231-2:2012 (Amended 2016)
[NW-D] • For UL: UL 1492:1996 (Amended 2013)
[NW-G] • Electrical equipment for measurement, control, and laboratory use; current measurement circuits in damp conditions: IEC 61010-1:2010+ A1:2016
Leak current measurement Ground leak current, 3 types of contact current, 7 types of patient leak current, patient measurement current, 4 types of total patient leak current, free current measurement, 3 types of enclosure leak current
Measurement current DC, AC (true rms, 0.1 Hz to 1 MHz), AC+DC (true rms, 0.1 Hz to 1 MHz), AC peak (15 Hz to 1 MHz)
Measurement ranges DC / AC / AC+DC mode: 50.00 mA/ 5.000 mA/ 500.0 μA/ 50.00 μA
AC peak mode: 75.0 mA/ 10.00 mA/ 1.000 mA/ 500.0 μA
Measurement accuracy
(current measurement)
DC measurement: ±2.0% rdg. ±6 dgt. (typ.)
AC / AC+DC measurement: ±2.0% rdg. ±6 dgt. (15 Hz to 100 kHz, typ.)
AC peak measurement: ±2.0% rdg. ±6 dgt. (15 Hz to 10 kHz, typ.)
Interfaces External I/O, medical device relay output, USB 1.1 (communications), RS-232C
Functionality 110% voltage application, automatic test, data storage for 100 target devices, clock, data backup, printed output (optional), etc.
Power supply 100/120/220/240 V AC (specify at time of order), 50/60 Hz, 30 VA rated power
Target device power supply input 100 to 250 V AC, 50/60 Hz Rated current input from terminal block: 20 A
Target device power supply output Output from terminal block: 20 A Output from outlet: 15 A
Dimensions and mass 320 mm (12.60 in)W × 110 mm (4.33 in)H × 253 mm (9.96 in)D, 4.5 kg (158.7 oz)
Included accessories Test lead L2200 (for ST5540, Red ×2, Black ×1) ×1 set, Enclosure probe 9195 ×1, Power cord ×3, Spare fuse for measurement line ×1, Instruction manual ×1, CD-ROM ×1

ST5540, ST5541 List of functions (Network)

Item ST5540 ST5541
Network A
(Electrical Appliances and Materials Safety Act)
Network B (Medical-use electrical devices) -
Network C (IEC 60990)
Network D (UL)
Network E (General-purpose 1)
Network F (General-purpose 2)
Network G (IEC 61010-1)

List of functions (Major functions)

Item ST5540 ST5541
Power on polarity switching function
Rated current 20 A
Function for checking for blown fuses
Frequency band switching -
110% voltage output terminal (T3 terminal) -
S10, S12, S13, E terminal -

List of functions (Testing leakage current mode)

Item ST5540 ST5541
Earth leakage current
Touch current
Patient auxiliary current -
Patient leakage current -
Total patient leakage current -
Free current
Enclosure - Earth leakage current
Enclosure - Enclosure leakage current
Enclosure - Line leakage current
Patient leakage current I -
Patient leakage current II -
Patient leakage current III -

Test probes (2)

*The L2200 (for ST5540, Red ×2, Black ×1) ×1 set and the 9195 are bundled

Printer options (2)

PC communications (1)


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