User Manual

Model 3760
10-Channel High Current Multiplexer Card User's Manual Section 4:
Operation considerations
3760-900-01 Rev. A / July 2017 4-3
Inductive loads
Inductive reaction voltage, L(di/dt), must be less than 500 V. Typical clamping circuits are shown in
the next figures. Also, consider the maximum load of 100 VA when determining the voltage limit. For
example, when switching 400 mA, the voltage must be limited to 250 V (V = 100 VA/400 mA) and the
clamping resistor calculation in the next figure would be:
R = V/I = 250 V/400 mA = 625 Ω
Figure 7: Model 3760 Limiting inductive reaction voltage
Make a modification
Unselected inputs on the 3760 high current multiplexer card are shorted (HI to LO) using installed
jumpers (R201 - R210). If isolation is required between channel LO and channel HI the 3760 can be
modified to disconnect channel LO from channel HI when a relay is off (open). The modification
involves removing a jumper wire for the channel that is to be modified. For example, remove jumper
R201 to disconnect channel one’s HI terminal from channel one’s LO terminal.
It is recommended to remove the jumpers by cutting them with a pair of wire cutters.