ALTER PM 740 T, Техническая заметка

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PM 740 T
page 6 of 21
File: PM740T_r3eng - Settembre 2004 - Manuale per: PM 740 T
PM 740 PM 740
PM 740 T
File: PM740T_r3eng - Settembre 2004 - Manuale per: PM 740 T
page 7 of 21
V) The
high voltage output
from the main unit must be
connected to the magnetron head by connector #3 and must
be connected to magnetron’s anode, usually marked with the
symbol “FA” on the magnetron’s teminal.
This voltage is near
3.5 kV
.
Use a proper insulated cable with working voltage >5 kVdc
and minimum gauge of 0.25 mm²; protect the wire with shea-
thing (armoured if possible).
The reliability of the system begins with the high voltage con-
nection so this cable must be assembled professionally.
ALTER can supply the HV cable with length on request.
VI) the connector #4 provides the power supply for the filament
transformer (usually located near the magnetron), the magne-
tron fan and a warning lamp. Use wires with a max gauge 1.5
mm². Refer to the wiring diagram on page 16;
VII) The “D” type female connector #5 has 25 pins and brings
the I/O signals to the equipment. We suggest shielded ribbon
cable is used for this purpose.
Refer to wiring diagram on page 17.
VIII) The “D” type female connector RS232 has 9 pins and
is a standard serial port. It can be used to upgrade the PM740
software using a PC. The pin-out connections are given on
page 18.
IX) the user must provide an external cut-off device, to protect
the PM740 from short-circuit and thermal runaway conditions;
this external protection device must also allow the main line to
be isolated for maintenance operations;
X) the external circuit breaker must be a 3-pole breaker and
must comply with EN61010-1 specifications;
XI) the external circuit breaker must be in close proximity to
the equipment and within easy reach of the operator;
XII) the external circuit breaker must be marked as the discon-
necting device for the PM740;
XIII) the connector #1 must never be used as a switch-off
device.
Failure to comply with these instructions may involve
considerable risks for the staff responsible for checking and
using the equipment, as well as the risk of general malfunc-
tions of the equipment itself.
Equipment operation
Power-up procedure
Before powering-up the equipment you must be sure to have
properly connected (look at the chapter “Wiring Instruction”
in case of any doubt), then set the front panel breaker in “ON”
position, marked with “1”.
Once set to OFF (position “zero”) wait at least five seconds
before setting it ON again.
This rule must be applied even in case the power is switched by
an external contactor (and the panel breaker has always left in
ON state): the OFF state, between two consecutive ON state,
must last 5 seconds.
At power on the unit enters into “POWER-ON” state for few
seconds to performs some internal checks and then goes imme-
diately into “STAND-BY” and remains in this state until the
“hibernate” command is switched OFF.
It’s also possible to permanently disable the “hibernate” com-
mand: in this case the PM740 performs the filament heating
immediately after the “POWER-ON” state, provided there are
no alarm conditions present.
At the end of the heating cycle the unit enters the “READY”
mode: the power supply may now power the magnetron to
generate microwave when it receives the enable command.
Any type of alarms will force the unit to exit the “READY”
state and to enter the “ALARM” state.
In absence of any alarm the power supply may be left in the
“Ready” state continuously: when it receives the enable com-
mand (ON) it enters into “RF-ON” state and generates output
power, when the enable command is removed (OFF) the unit
comes back to the “READY” state.