Zener MSC-3, Инструкция по эксплуатации

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IM00120 51 IM00120
MSC-3 Instruction Manual
Dual Ramps
For applications that use a minimum speed, the MSC-3 provides a dual rate acceleration and
deceleration. The
C033 DUAL RAMP
option provides this feature. When enabled the rate of acceleration
and deceleration in the speed range 0 to B03 MOTOR Hz is at a rate of B03 MOTOR Hz/C032 S TIME.
The diagram below shows the reference as a function of time. Refer to C033 DUAL RAMP for details.
C010 MIN Hz
Speed
Time
Reference
Slope =
B03 MOTOR Hz / C032 S TIME
Slope = B03 MOTOR Hz / C030 ACCEL TIME
Slope =
B03 MOTOR Hz / C031 DECEL TIME
Key ramp configuration parameters are:
• C033 DUAL RAMP (function activation)
• C032 S TIME
• C030 ACCEL TIME
• C031 DECEL TIME
• B03 MOTOR Hz
Essential Services Override
There are circumstances in some applications for which it is desirable to disable certain of the protective
features of the MSC-3. These are situations where continued operation has a higher priority than
preventing damage to the MSC-3 or associated motor. A typical example is a building air conditioning
application in which a fan is required to operate as part of a smoke clearance system. Various standards,
for example, AS/NZS 1668.1:1998: The use of ventilation and air conditioning in buildings - Fire and
smoke control in multi-compartment buildings require that all thermal protection be disabled during
operation in a smoke clearance mode and equipment allowed, if necessary, to run to destruction. The
MSC-3 provides a special mode, Essential Services Override (ESO), to give effect to these requirements.
Operation in ESO requires a control terminal to be configured for the ESO function and that this terminal
to be connected to +5V (terminal 1) whenever ESO operation is required. During ESO operation the
MSC-3 is forced to run and the following protective functions are disabled:
• Heat sink over temperature protection
• I2t protection
• Motor thermistor protection (if fitted)
• Supply Fail
In addition, the Auto Restart function is automatically enabled with unlimited auto restarts permitted.
In order to allow the MSC-3 to be independently optimised for both the usual operating condition and
operation in ESO mode, separate parameters are provided for ESO and non ESO operating modes.