Wintriss Shadow 8, Руководство пользователя

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1139300 Shadow 8 User Manual
D-20 Extracts from OSHA and ANSI
drive system. This time should take into consideration both uncontrolled stops (category 0)
and controlled stops (categories 1 and 2) including dynamic braking. See ANSI / NFPA 79.
Note 5: The stopping time, Ts, of machines actuated or controlled by pneumatic or hydraulic valves
must include the reaction time of the valve measured from the time that the valve is de-
energized until motion is stopped. Stopping time for systems using valves may be affected
by high or low supply pressures, exhaust restrictions, sluggish spools or poppets or
performance of the pilot sections.
Note 6: Control systems inherently have a delay from the time its inputs or the system logic initiate a
stop command, until the system's output de-energizes the actuator. This time, Tc, is the
reaction time of the control system.
Note 7: Safeguarding devices also have a delay from the time that they sense the presence, or
absence (for hand controls and trips or hostage controls) of individuals. Additionally, there
may be a delay caused by the interface between the device and the control system. The
interface may, as an example, include interposing relays. The interface delay must be added
to the total delay time. This time, Tr, is the reaction time of the device and its interface. The
reaction time of the device, without the interface, is stated by the device manufacturer.
Note 8: Stopping performance monitors are used to assure that a gradual increase in the stopping
time caused by the degradation of components does not exceed the stopping time used to
calculate the safety distance for the safeguarding device. Stopping time at the end of a
machine cycle is usually different than the stopping time during the hazardous portion(s) of
the cycle, and since these times may vary due to such factors as machine temperature, tool
loading and energy transferred to the workpiece, a factor, Tspm, must be added to the total
stopping time.
Tspm is a calculated factor. As an example, if the monitor is set to a point or time 5% greater
than the normal stopping position or time, then Tspm is equal to 5% of Ts.
Therefore, the total stopping time is the sum of these factors and may be represented by the following
equation:
T = Ts + Tc + Tr + Tspm
Equation (5)
Stop time measuring devices are normally used to measure these times. When using these devices,
Ts can be measured from the output of the control system until motion is stopped. Likewise, Ts + Tc
can be measured from the input to the control system. Some stop time measuring devices include
plungers and flags that are used to simulate operation by an individual. When using this type of device,
it is possible to measure Ts + Tc + Tr. (Use the manufacturer's value for Tr, when provided).
Substituting Ts + Tc + Tr + Tspm for T in Equation 1, the equation for calculating the safety distance
becomes:
Ds = K (Ts + Tc + Tr + Tspm)
Equation (6)
An additional distance needs to be added to the safety distance when using electro-optical devices,
safety mats, single control safety devices and RF devices.
Electro-optical and RF devices do not detect the presence of individuals at the plane or within the field
of the device until an amount of penetration into the plane or field occurs. This amount is known as the
distance (depth) penetration factor. The distance that must be added is called Dpf. See Figures D.1 --
D.6 and D.9.
When using safety mats and single control safety devices, it is possible for the individual to be
reaching into the hazardous area or stepping onto the mat beyond its edge. The amount of reach or
stride should be added to the safety distance and can be called Dpf. See Figures D.2, D.6 and D.7.
The equation for calculating the safety distance for these devices, therefore, is:
Ds = K (Ts + Tc + Tr + Tspm) + Dpf
Equation (7)