Emerson FXMP25 User Manual

54 FXMP25 User Guide
www.controltechniques.com Issue Number: 3
8.4 AC supply requirements
The FXMP25 is rated for a nominal supply up to 480 Vrms.
8.4.1 Supply types
The FXMP25 is suitable for use with any supply type, i.e. TN-S, TN-C-S, TT, IT, with
grounding at any potential, i.e. neutral, centre or corner (grounded-delta).
8.4.2 AC supply specification
Table 8-2 AC supply
8.5 Line reactors
The FXMP25, in common with all naturally commutated SCR drives, causes voltage
notches at the input supply terminals. To avoid disturbances with other equipment using
the same supply, the addition of external line inductance is strongly recommended in
order to restrict the depth of notches imposed. This is generally not necessary where a
dedicated transformer is used to supply the FXMP25.
The following recommendations for added line inductance, have been calculated based
on the power drive systems standard: EN 61800-3:2004 "Adjustable speed electrical
power drive systems - Part 3: EMC requirements and specific test methods".
Table 8-3 Minimum values of L
add
and inductor current rating for a typical
application
Specification Product voltage variant
Maximum nominal supply 480 V
Tol er an ce 10 %
Minimum nominal supply 208 V
Tol er an ce -1 0 %
Field output
current
System voltage Typical current
rating
400 V 480 V
A μH μH A
25 230 290 26
On typical field windings or high inductance loads the output current is smooth DC and
therefore the rms input current is approximately equal to the DC output current.
The above assumes the supply has 1.5 % impedance and a minimum supply rating of
5 kA.
NOTE
Control of currents below 250 mA (thyristor holding currents) should be avoided. If
control at this level is required then line reactors must be installed to reduce the effect
of dv/dt as thyristors turn off.
CAUT ION

Emerson FXMP25 Specifications

General

Brand	Emerson
Model	FXMP25
Category	Controller
Language	English