Fronius DeltaSpot, Инструкция по эксплуатации/Перечень запасных частей

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Recommended cooling water quality:
Transformer PE
conductor con-
nection Fronius medium-frequency transformers conform to protection class 1.
The medium-frequency transformer is supplied with the additional safety feature of a "di-
rect PE conductor connection" as follows:
-
Detachable PE conductor bridge (MPE) between the secondary circuit of the medium-
frequency transformer and the transformer's PE conductor connector
If an alternative approved safety system is implemented:
Remove PE conductor bridge (MPE)
Indicate removal of PE conductor bridge (MPE) permanently on the transformer.
The "direct PE conductor connection" safety measure can cause compensating currents
that can have negative effects on welding quality. To prevent this, a floating secondary cir-
cuit is required in conjunction with another safety measure according to EN 62135-1.
NOTE! Inadequate cooling can cause damage to property. Never operate weld-
ing plant without adequate cooling. The manufacturer shall not be liable for dam-
age caused by inadequate cooling.
NOTE! The system operator must ensure that the coolant is prefiltered through a
coarse, 5µ filter.
IMPORTANT! We recommend fitting water-cooled components with flow controllers. The
switching point of a flow controller on a gun arm is approx. 4.0 l/min (1.0 gal./min). The
switching point of a flow controller on a transformer can be found in the transformer data
sheet.
IMPORTANT! The flow temperature of the coolant should be 20 °C (68 °F)! The minimum
flow rate should be 16 l/min at 3 bar differential pressure.
pH value 7 to 8.5
Hardness grade D
max
10 German degrees, 12.5 English degrees
10.5 US degrees, 18 French degrees
Chloride max. 20 mg/l
Nitrate max. 10 mg/l
Sulphate max. 100 mg/l
Insoluble substances max. 250 mg/l
CAUTION! Risk of condensate causing short-circuit. Water-carrying parts should
be isolated to prevent condensate from leaking out. Note the information provided
by the manufacturer of the cooling system.
NOTE! Additional safety precautions are required for medium-frequency trans-
formers in protection class 1 to guard against an isolation failure between the pri-
mary and secondary power circuits. National and international standards and
guidelines must be observed. The plant operator is responsible for the implemen-
tation and operation of the system.
DANGER! Possible inadmissible contact voltages due to compensating currents!
If compensating currents are unavoidable in the case of "direct PE conductor con-
nection", use fault voltage or fault current protective circuits designed to operate
on 1000 Hz medium-frequency systems with a direct current intermediate circuit.
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