Baldor MN850 Connection Descriptions, UL Required Fuses for Short Circuit Rating, Catalog Number

UL Required Fuses for Short Circuit Rating

UL requires R/C fuses, special purpose fuses (JFHR2) or semiconductor fuses rated 700VAC be used to obtain the short circuit current ratings required by UL.

	Fuse Manufacturer		Fuse	Short Circuit Rating
Model Number	Bussman (300 KA A.I.C.)	Ferraz (200 KA A.I.C.)	Current Rating	Amperes
	Catalog Number	Catalog Number	Amperes
MD9 to MD16	170M3110	6.6 URD 30 D08 A 0063	63	5,000
MD23 to MD30	170M3112	6.6 URD 30 D08 A 0100	100	5,000
MD44	170M3114	6.6 URD 30 D08 A 0160	160	5,000
MD59	170M3115	6.6 URD 30 D08 A 0200	200	5,000
MD72 to MD85	170M3116	6.6 URD 30 D08 A 0250	250	10,000
MD105 to MD146	170M3119	6.6 URD 30 D08 A 0400	400	10,000
MD174 to MD202	170M3121	6.6 URD 30 D08 A 0500	500	10,000
MD242	170M4114	6.6 URD 31 D08 A 0500	500	10,000
MD300	170M4114	6.6 URD 31 D08 A 0500	500	18,000
MD370	170M4116	6.6 URD 31 D08 A 0630	630	18,000
MD500	170M6113	6.6 URD 33 D08 A 0900	900	18,000
MD600	170M6113	6.6 URD 33 D08 A 0900	900	30,000
MD750	170M6116	6.6 URD 33 D08 A 1250	1250	30,000
MD900	170M6116	6.6 URD 33 D08 A 1250	1250	42,000
MD1100	170M6116		1500	42,000
MD1200	(2) 170M6116		(2) 1000	42,000

Main Input Contactor An IEC or NEMA rated contactor is recommended at the input power to the control. The soft–start control uses three pairs of SCR (silicon controlled rectifier) semiconductor devices that do not positively disconnect power. Figure 2-1 shows that the input contactor provides a positive disconnect.

	Table 2-2 Connection Descriptions
Terminal	Description
L1, L2, L3	Input AC power terminals. Connect input isolated 3 phase supply (any phase to any terminal).
T1, T2, T3	Output Power Terminals. Connect an induction motor to these terminals. For correct motor rotation,
	connection of these phases must correspond with the supply connections (L1, L2, L3).
X1, X2	Control Supply Input. The internal circuits require power from a 115VAC or 230VAC source (Table 2-3).
	A selector switch is provided to select the voltage range of the source that is connected to this input.
	Remote Start/Stop Input. A voltage present across these terminals will initiate a “Start”.
S1, S0	Removing the voltage from across these terminals will initiate a “Stop”.
	Note that the factory setting is keypad Start/Stop.
Relay K1	Pins 11 and 12 are the	normally closed “Run” relay contacts.
	Pins 11 and 14 are the	normally open “Run” relay contacts.
Relay K2	Pins 21 and 22 are the	normally closed “Top of Ramp” relay contacts.
	Pins 21 and 24 are the	normally open “Top of Ramp” relay contacts.

MN850 Installation 2-5