ESAB LHF 400, Instruction Manual

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3 INTRODUCTION
LHF 400/630/800 are thyristor controlled welding rectifiers designed for welding with
coated electrodes and TIG welding.
The welding rectifiers can be used with the following remote control devices:
PHA 1, PHA 2, PHA 5, PHB 1, PHB 2, och PHC 2.
An auxiliary control unit is required for TIG welding with high frequency arc ignition.
LHF 400/630, versions with meters and timed cooling fan.
These welding rectifiers are equipped with a volmeter, ammeter and a circuit that
reduces the idle speed of the cooling fan.
The meters allow current and voltage settings to be read from the front of the
rectifier.
To minimise the amount of dust and dirt that is drawn into the rectifier the fan runs at
a reduced idle speed of 300 rpm. When welding with currents greater than 30 A the
fan speed increases to its working speed of around 1350 rpm. A timer relay
maintains the higher speed setting for 6 1/2 minutes after welding has stopped to
ensure adequate cooling of the rectifier.
4 TECHNICAL DATA
LHF 400 LHF 630 LHF 800
Maximum load
35 % duty cycle 400 A/36 V 630 A/44 V 800 A/44 V
60 % duty cycle 315 A/33 V 500 A/40 V 630 A/44 V
100 % duty cycle 250 A/30 V 400 A/36 V 500 A/40 V
Setting range 8A/20V--400A/36V 8A/20V--630A/44(49)
V
8A/20V--800A/44(50)
V
Open circuit volt. 80--87 V 65--72 V 65--72 V
Open circuit output
at 400 V 340 W 615 W 640 W
Power factor
(max current) 0,90 0,87 0,82
Efficiency
(max current) 74 % 77 % 78 %
Enclosure class IP 23 IP 23 IP 23
Application class
Weight 195 kg 260 kg 295 kg
Dimens. lxwxh 1310/765/705 1310/765/705 1310/765/705
Duty cycle
The duty cycle refers to the time as a percentage of a ten--minute period that you can weld at a cer-
tain load without overloading.
Enclosure class
The IP code indicates the enclosure class, i. e. the degree of protection against penetration by solid
objects or water. Equipment marked IP23 is designed for indoor and outdoor use.
Application class
The symbol indicates that the power source is designed for use in areas with increased
electrical hazard.
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