HP 212A - 2-3 Automatic Overload Relay Protection

PULSE WIDTH
The PULSE WIDTH control is the large dial at the center of the panel
and controls the width of the MAIN OUTPUT pulse.
AMPLITUDE
The AMPLITUDE control gives a continuous variation af the MAIN OUT-
PUT pulse.
ATTENUATION
The ATTENUATION control, located an the right hand side of the panel,
provides attenuation of the Main pulse in 10 db steps so that low levels
of pulse output can be obtained.
POLARITY
The POLARITY'control at the lower right hand side of the panel switches
the polarity of the MAIN OUTPUT pulse from positive to negative.
FUSE
The fuseholder,
on the panel next to the POWER ON switch, contains a
4 ampere cartridge fuse.
A 2 ampere fuse should be used when the
power transformer is connected for 230V operation.
The fuse may be
replaced by unscrewing the fuseholder cap and inserting a new fuse.
2-3 AUTOMATIC OVERLOAD RELAY PROTECTION
An overload relay is incorporated in the instrument to protect the @ 45~
thyratron if, for any reason, continuous plate current conduction occurs.
Operation of the relay is indicated by a buzzing sound,
If this occurs
when the instrument is first turned on, it may indicate that there is in-
sufficient warm-up and turning the SYNC SELECTOR to the + or - po-
sition without any external triggering for two or three minutes should
then place the instrument in normal operating condition.
The Model 21ZA Pulse Generator is operated as follows:
1.
Plug the power cable into a nominal 115V, 50 to 60 cycles power
line and turn on the toggle switch.
(The pilot lamp should light
when the swftch is on. )
2.
Allow several minutes for the instrument to warm up with the SYNC
SELECTOR in the t or - position and with no sync in, Although the
unit can be used after 2 or 3 minutes of warm up, it is desirable to
allow about ten minutes warm up time if possible.
3.
Connect the equipment to be driven to the PULSE OUT terminal.
This connection should be made, if possible, through a nominal