Breas PV 101+, Service Manual

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ELECTRONICS PV 101+/PV 102+ Service Manual
7–8 BREAS MEDICAL Doc. No. 003259 En Issue: X-1
7.5 Electrical safety measurements
Electrical safety measurements must be made in accordance with EN 60 601-1. How-
ever, you can make an insulation resistance measurement instead of the voltage test
specified by the standard. The measurements can be made using an automatic electri-
cal safety tester. All tests must be performed in accordance with class II type BF.
Supply voltage
• Note the power voltage reading.
The voltage must be noted for each service check, as the currents measured are
directly in relation to the supply voltage. This allows all measurements made on the
same machine to be compared with measurements made on different occasions.
Insulation
• Measure the insulation resistance using a 500V DC power supply.
The most suitable method is to connect the plus lead to the two ventilator power socket
pins and the minus lead to the casing or patient air connector.
The measurements made during the delivery inspection can be used as reference val-
ues for measurements made during future services. If no reference values are available,
the value for the insulation resistance should be >20M
Ω
.
Leakage currents
• Measure the leakage currents at different parts of the ventilator using an RC circuit
to ground.
The measurements are made partly at normal case (NC) and at the single fault condi-
tion (SFC). Reverse the polarity of the power supply and note the highest value.
The leakage currents to ground must not exceed the stated limit values.
Leakage currents from the casings
• Measure the leakage current of the casing at an unpainted point, for example, the
head of a screw.
Limit values: NC < 0.1mA
SFC < 0.5mA
Break neutral for SFC.
Patient leakage currents
• Measure the patient leakage currents between the patient connector and ground.
Limit values: NC < 0.1mA
SFC < 0.5mA
Break neutral for SFC.
Leakage currents with mains power supply at the patient connected part
• Perform this test using an automatic electrical safety tester with this function.
See the safety instructions for the tester.
Limit value: SFC < 5mA