bonitron Legacy M3534R-RY, Руководство для пользователей

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User’s Manual
17
4.
O
PERATION
4.1. F
UNCTIONAL
D
ESCRIPTION
The M3534R series of Ride-Thru Modules (RTMs) employs IGBT switching
technology to regulate the inverter DC bus to a preset minimum voltage level. As the
incoming AC voltage level drops, the RTM “activates”, boosting a rectified DC voltage
up to the minimum DC bus voltage level specified for the inverter,
allowing it to “ride
through” the sag or outage event.
Upon application of power to the M3534R, its DC bus will begin to precharge via
internal PTC surge limiters. When the bus reaches 150VDC, the internal logic power
supply of the RTM will begin switching, and will supply the +24V and ±15V DC needed
to power the control circuitry. At this point the PWR LED will illuminate. In addition,
the RTA relay within the RTM and its corresponding RTA LED may turn on briefly
during the RTM’s precharge period. Once the RTM’s DC bus has fully precharged to
its preset nominal value (see Ratings chart in Table 6-2 for voltage levels), the control
module’s PWR LED will be ON, and the RTA and OVERTEMP LEDs will be OFF. The
RTM is now ready to protect the inverter system from voltage sags up to and beyond
SEMI-47 conditions.
During a voltage sag or outage, the inverter DC bus level will decrease, pulling the
RTM bus down with it.
Once the DC bus drops below a preset low limit “threshold” the
RTM will become “active”. When this occurs, the RT ACTIVE front panel LED will
illuminate, the internal RTA relay contact will change states, the cooling fan will begin
running in order to cool the internal IGBT heatsink, and the DC bus level will be
supported by the RTM. The RT ACTIVE LED and internal relay will be
ON only while
the RTM is active (real time). The cooling fan will continue running for 2 minutes after
activity stops. A special Kinetic Buffering option will hold off an externally generated
KB signal until the RTM can no longer maintain threshold DC bus level.
If the RTM begins supplying power continuously, possibly due to a low line level,
incorrect threshold adjustment, or inverter fuse failure, an over temperature condition
may occur. If this happens, the OVERTEMP front panel LED will turn ON and the
internal OT relay will energize, shutting down the switching circuits and allowing the
DC bus to drop to the nominal level. At this point, the RTM will continue supplying
power, via an internal bridge rectifier, at the nominal line level.
If the sag duration exceeds 50% while the RTM is fully loaded, the output DC bus level
will begin to drop.
If the inverter’s LOW BUS trip level is reached, the inverter will shut
down.
When the DC bus drops to 100V, the RTM’s internal logic supply will shut down.
Figure 4-1: Basic 40A & 85A M3534R RTM Internal Power Flow Circuit Diagram
Dwg: 060157 Rev 20090325