General Information; Safety And Preparation For Use - Stanford Research Systems SIM910 Operating Manual

General Information

Safety and Preparation for Use

Biomedical Applications
WARNING
Regarding Use with Photomultipliers
CAUTION
Service
The SIM910 JFET Preamp, part of Stanford Research Systems' Small
Instrumentation Modules family, is a low noise general purpose volt-
age preamplifier with bandwidth from DC to 1 MHz.
Under certain conditions, the SIM910 may prove to be unsafe for
applications involving human subjects. Incorrect grounding, com-
ponent failure, and excessive common-mode input voltages are ex-
amples of conditions in which the instrument may expose the subject
to large input currents. Therefore, Stanford Research Systems does
not recommend the SIM910 for such applications.
The front-end amplifier of this instrument is easily damaged if a
photomultiplier is used improperly with the amplifier. When left
completely unterminated, a cable connected to a PMT can charge
to several hundred volts in a relatively short time. If this cable is
connected to the inputs of the SIM910, the stored charge may damage
the front-end JFETs. To avoid this problem, provide a leakage path of
about 100 k to ground inside the base of the PMT to prevent charge
accumulation.
Do not install substitute parts or perform any unauthorized modifi-
cations to this instrument.
The SIM910 is a single-wide module designed to be used inside the
SIM900 Mainframe. Do not turn on the power until the module is
completely inserted into the mainframe and locked in place.
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