Time Electronics 5051 Plus - General Safety Precautions; General Operation Precautions

Time Electronics User Manual
5051 Plus and 7051 Plus Multifunction Calibrators v2.1
xx51+ Multifunction Calibrators Page 9 of 64
3. General Safety Precautions
High Voltage: The xx51 can produce 1050 V and users should be aware of the dangers
involving serious electrical shock.
High Current: The xx51 can produce 22 Amps and users should be aware of the power
levels involved. Equipment connected to the 5051 should be capable of withstanding the
currents involved without damage. High current outputs, greater than 10A, should not be
left on for periods longer than 10 minutes.
4. General Operation Precautions
Prior to using the xx51, the following precautions and recommendations should be noted.
o The xx51’s outputs are protected against short circuit, but serious internal damage can occur if
voltage or current is injected into output terminals.
o The xx51’s output terminals are floating with respect to mains earth (the green terminal on the
front panel). The negative output terminals can be allowed to rise to a maximum of +/-75V with
respect to earth. For certain calibrations it will be found beneficial to earth the low (negative)
output terminal. This will prevent noise pickup and will generally improve the stability of readings
if the unit under calibration is not earthed.
o Earthing the xx51’s high (positive) terminals is prohibited.
o The user should always be aware of the dangers of high voltage. The xx51 can produce 1000V
AC, which is approximately 1600V peak. Voltages of this level present a serious electrical shock
hazard to the user. Care should be taken to ensure that voltages above 50V are switched off
before the user touches the test leads.
o Certain types of equipment will be found to be susceptible to electrical noise pickup at the
frequency of the main power supply. Generally, this sort of equipment should be calibrated at a
different frequency.
o The precision resistors used for the passive resistance function are suitable for operation at low
currents. Care should be taken not to overload them, since permanent damage can result. The
max allowed currents are, 10mA up to 1kΩ, 1mA for 1k – 10kΩ, 0.1mA for 10k – 100kΩ, and
10uA above 100kΩ.
o When using the high current (20A) terminals, ensure that good quality low contact resistance
connectors and leads with adequate current carrying capability are used. The 9542 General
Purpose Test Leads are rated to 32 A and designed for this application.
o To clean use an alcohol-free wipe such as a ‘durable screenclean 50’