bonitron M3460R, Customer Reference Manual

Recommended Input Power Wiring Sizes And Power 

Source Fusing For Model M3460R Cabinet Mounted And 

Rack Mountable Open-Chassis Ride-Thru Systems 

 doc.#993004 

  7/18/2000

The following data is supplied for assistance in selecting the appropriate field wiring sizes and 

power source fuse ratings for the model M3460R Cabinet Mounted and Open-chassis Ride-Thru 
systems. 

For cabinet mounted systems, the customer power terminations for the 3

∅

 AC line and DC 

bus are provided on the left side of the cabinet’s ‘disconnect panel’ which is mounted inside at 
the upper rear of the cabinet. A ‘Ground’ termination is also provided and is located on the left 
side of the cabinet just below the disconnect panel. Refer to 

Typical Rack Disconnect Panel 

Layout

 drawing# 990255

.

For rack mountable open-chassis systems, Customer power wiring connections to the 3-phase 

AC line and DC bus are provided at one end of the Ride-Thru chassis.  The 3-phase AC and DC 
bus inputs are connected directly to the corresponding fuse mounting terminal. A ground terminal 
is provided on the backplate. Refer to

 Typical Open Chassis Field Connections Layout

 drawing# 

000205

.

Please note that the input power source and power wiring supplied to the M3460R Ride-

Thru system must be capable of providing a 2-second surge at twice the rated power of the 
Ride-Thru system.

Steady state CLASS J TIME DELAY or equivalent power source fusing should be used to 

support the requirement for 2-second surge capability at twice the rating of the Ride-Thru. The 
recommended minimum current rating for the power source fusing is listed in Table-1 below 
based on the DC bus current rating of the Ride-Thru module. The maximum rating of the steady 
state power source fusing should be 

≤

 225 amps for cabinets with disconnects. 

The field wiring sizes listed in Table-1 below assure a 

≤

10V drop for wire lengths of 

≤

100 

feet and are compatible with the recommended steady state power source fusing listed. The wire 
gauge selected for field wiring to the Ride-Thru should be equal to or greater than that listed in 
Table-1. The maximum wire gauge that can physically be accepted by the cabinet disconnects is 
4/0.  

Table 1 

Ride-Thru DC Bus 

Current Rating 

Minimum Source Fusing 

(Class J Time Delay) 

Recommended Field 

Wiring Sizes 

75 Amps 

70 Amps 

2 AWG 

120 Amps 

100 Amps 

2 AWG 

160 Amps 

125 Amps 

1 AWG 

240 Amps 

175 Amps 

2/0 AWG 

320 Amps 

225 Amps 

3/0 AWG