DC/AC Inverter
INV222 & INV211
User Manual
Page 6 (20)
©2014. ELTEK DEUTSCHLAND GmbH.
Eltek_UM_INV222_and_INV211_E_R2.0.doc
3. General information
The inverter INV222 (INV211) converts input side DC voltage to a stable sine wave output voltage.
The INV2xx is a module with rear side connectors and is designed to be mounted in an assembly set sub rack
(see
section 4.2
).
The inverter is controlled and monitored by internal microprocessors. Due to its state-of-the-art circuitry design,
the unit has very low losses and consequently, compact dimensions, low weight and a very high power density.
To increase the reliability the inverter is designed to operate in combination with a static transfer switch of the STS
model range. The static transfer switch monitors the connected bypass mains and synchronizes the inverter out-
put with mains frequency and phasing as well. The static transfer switch's default setting is "inverter priority"
mode. That means the load is fed via STS by the inverter(s). But in case of inverter faults, high overload or battery
low voltage, the STS switches the load supply to bypass mains nearly without interruption (<4 ms). The unit
switches back to inverter operation automatically if the reason for switch-over is gone. In case of mains priority
mode (optionally) the inverter(s) take over the load if the mains voltage is not present, out of limit or heavily dis-
turbed. The priority source is programmable at the STS unit (see appropriate manual).
The nominal output power of the INV222 unit is 1.8 kW/2.25 kVA at an output voltage value of 230 VAC (INV211:
0.9 kW/1.1 kVA at an output voltage value of 115 VAC). A maximum of 20 modules
1
without static transfer switch
can be switched in parallel to increase the system output power or to build redundant power supply systems (n + x
principle).
INV222 for
three-phase
applications are available on request (see
Appendix
).
3.1 Typical applications
Figure 1. Inverter in parallel operation without STS
Figure 2. Inverter in parallel operation with STS
1
INV211/222-48V/60V/110V: From hardware release 03; INV211/222-220V: From hardware release 02