Exlar Tritex II DC Series, Инструкция по установке и обслуживанию

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Curtiss-Wright | Tritex II DC Rev. J PN49220 2/8/2016 27
Power from Battery Systems
Tritex II DC is designed to be powered directly from 12V and 24V lead-
acid batteries in vehicles. Regen energy and ripple current are not
generally of concern with battery applications of this type. Battery
systems generally will be able to supply peak power to the actuator. The
average power may be a consideration in sizing the charging circuits for
the battery system. Other battery powered applications are possible, but
would require additional engineering considerations.
The product has not been tested for immunity to “load dump”
conditions. An external voltage clamp designed specifically for load
dump protection may be necessary on 24V systems.
Handling Regen Energy
– Internal Shunt Resistor and Regulator
Tritex II DC has a built in controller and small internal shunt resistor
that can handle up to 10 joules of energy at a time as long as average
power does not exceed 8W. Though not high capacity, it is adequate to
handle the inertia for many linear and geared applications and for some
low-inertia rotary applications. It is usually inadequate to handle energy
from a vertical load or spring return. The controller will turn off the shunt
upon reaching either energy or power limits. If there is more regen
energy, the bus voltage will rise, resulting in a high bus fault.
Note: A poorly tuned system may have some oscillation that results in
the bus voltage pumping up and down enough to turn on the shunt. This
reduces the available capacity for handling expected energy from
deceleration. Likewise, if an overly aggressive move profile results in
significant following error, there can be velocity overshoot followed by
deceleration that causes unnecessary regen energy to reach the internal
shunt resistor.
As shipped from the factory the internal regulator is set to a value to
protect the Tritex from an overvoltage fault condition (85 V). This
parameter will not require adjustment as long as the power supply can
be back-driven to 85 V like most unregulated 48 V supplies, or can
handle all the regen energy like most battery applications, or is isolated
with a blocking diode. For other applications, the built in regulator can be
adjusted to restrict bus voltage to a level that will protect the power
supply from regen energy. Set the User Overvoltage Fault Limit
Parameter found in Expert software on the System Set-up page / Limits
tab to a value that the power supply can tolerate. The Tritex shunt
regulator will operate at 90% of the User Overvoltage Fault Limit value.
The drive will trip with a High Bus Voltage fault at the User Overvoltage
Fault Limit value or at 85 V, whichever is lower. The default setting of 0 is
a special case that means the factory parameter values of 85 V for trip
and 76.5 V for shunt operation will be used.
In the example below a single 24 volt supply is used to power bus,
logic and Field I/O, the logic power is derived internally from the bus
power, the 24 volt regulated supply will keep the I/O voltage under the