INPUT DATA	Fronius Symo 3.7-3-S	Fronius Symo 3.7-3-M
Max. input current (Idc max 1 / Idc max 21))	16.0 A / 16.0 A
Max. array short circuit current (MPP1/MPP21))	24.0 A / 24.0 A
Min. input voltage (Udc min)	150 V
Feed-in start voltage (Udc start)	200 V
Nominal input voltage (Udc,r)	595 V
Max. input voltage (Udc max)	1,000 V
MPP voltage range (Umpp min – Umpp max)	250 - 800 V	150 - 800 V
Number of MPP trackers	1	2
Number of DC connections	3	2 + 2
Max. PV generator output (Pdc max)	7.4 kWpeak	7.4 kWpeak
OUTPUT DATA
AC nominal output (Pac,r)	3,700 W	3,700 W
Max. output power	3,700 VA	3,700 VA
AC output current (Iac nom)	5.3 A	5.3 A
Grid connection (voltage range)	3~NPE 400 V / 230 V or 3~NPE 380 V / 220 V (+20 % / -30 %)
Frequency (frequency range)	50 Hz / 60 Hz (45 - 65 Hz)
Total harmonic distortion	< 3 %
Power factor (cos φac,r)	0.70 - 1 ind. / cap.	0.85 - 1 ind. / cap.
GENERAL DATA
Dimensions (height x width x depth)	645 x 431 x 204 mm
Weight	16.0 kg	19.9 kg
Degree of protection	IP 65
Protection class	1
Overvoltage category (DC / AC)2)	2 / 3
Night time consumption	< 1 W
Inverter design	Transformerless
Cooling	Regulated air cooling
Installation	Indoor and outdoor installation
Ambient temperature range	-25 - +60 °C
Permitted humidity	0 - 100 %
Max. altitude	2,000 m / 3,400 m (unrestricted / restricted voltage range)
DC connection technology	3x DC+ and 3x DC- screw terminals 2.5 - 16 mm²	4x DC+ and 4x DC- screw terminals 2.5 - 16 mm² 3)
AC connection technology	5-pin AC screw terminals 2.5 - 16 mm²	5-pin AC screw terminals 2.5 - 16 mm² 3)
Certificates and compliance with standards	ÖVE  / ÖNORM E 8001-4-712, DIN V VDE 0126-1-1/A1, VDE AR N 4105, IEC 62109-1/-2, IEC 62116, IEC 61727, AS 3100, AS 4777-2, AS 4777-3, CER 06-190, G83/2, UNE 206007-1, SI 4777 1), CEI 0-211), NRS 097
EFFICIENCY
Max. efficiency	98.0 %
European efficiency (ηEU)	96.7 %	96.9 %
η at 5 % Pac,r4)	83.4 / 86.4 / 80.6 %	81.6 / 87.8 / 82.8 %
η at 10 % Pac,r4)	90.1 / 92.5 / 88.7 %	87.9 / 93.6 / 90.5 %
η at 20 % Pac,r4)	93.7 / 95.7 / 93.6 %	91.9 / 96.0 / 94.1 %
η at 25 % Pac,r4)	94.5 / 96.4 / 94.7 %	92.9 / 96.6 / 95.2 %
η at 30 % Pac,r4)	95.0 / 96.7 / 95.4 %	93.5 / 97.0 / 95.8 %
η at 50 % Pac,r4)	96.9 / 97.6 / 96.7 %	94.6 / 97.7 / 96.8 %
η at 75 % Pac,r4)	96.2 / 97.8 / 97.3 %	95.0 / 97.9 / 97.4 %
η at 100 % Pac,r4)	96.2 / 98.0 / 97.5 %	95.1 / 98.0 / 97.5 %
MPP adaption efficiency	> 99.9 %
PROTECTIVE DEVICES
DC insulation measurement	Yes
Overload behaviour	Operating point shift, power limitation
DC disconnector	Yes
Reverse polarity protection	Yes
INTERFACES
WLAN / Ethernet LAN	Fronius Solar.web, Modbus TCP SunSpec,  Fronius Solar API (JSON)
6 inputs and 4 digital in/out	Interface to ripple control receiver
USB (type A socket)5)	Datalogging, inverter update via USB flash drive
2x RS422 (RJ45 socket)5)	Fronius Solar Net, interface protocol
Signalling Output5)	Energy management (floating relay output)
Datalogger and Webserver	Included
External Input5)	S0 meter connection / Evaluation of overvoltage protection
RS485	Modbus RTU SunSpec or meter connection

¹⁾ This applies to Fronius Symo 3.0-3-M, 3.7-3-M and 4.5-3-M
²⁾ Testing to IEC 62109-1.
³⁾ 16 mm² without ferrules
⁴⁾ And at U_{mpp min} / U_dc,r / U_{mpp max}
⁵⁾ Also available in the light Version.