4qd 4QD-300-36 Manuel d'instruction - Page 14

Parcourez en ligne ou téléchargez le pdf Manuel d'instruction pour {nom_de_la_catégorie} 4qd 4QD-300-36. 4qd 4QD-300-36 16 pages.

13 Output current and

Heatsinking

The available output current depends on the

temperature. A typical 4QD-300D controller, into a

stalled motor, will give between 300 and 330 amps

when cold, decreasing as the unit heats up until the

overheat thermostat cuts in. In normal operation, full

current will only be required intermittently in short

busts. However, the controller may warm up

gradually and, if the usage is particularly arduous,

the overheat thermostat will cut the controller off.

The time taken to overheat is load and mounting

dependant and is therefore not easily predicted, but

the heatsink supplied is adequate for most

requirements.

It is good practise if maximum lifetime is required,

for electronic equipment not to be allowed to run too

hot. Therefore, even if the overheat thermostat

doesn't cut the controller off, if the heatsink runs hot

to the touch then extra heatsinking may be required

or a higher current controller is indicated.

Page 14

14 Mounting and earthing

It is suggested that the electrical system not be

earthed to chassis. 4QD-series controllers are

isolated from the heatsink and the heatsink will

normally be bolted onto the vehicle's chassis. If the

system is floating a wiring fault that causes a short to

chassis will cause no damage, whereas if battery

negative is earthed then a short to earth in motor or

wiring would destroy the controller. Such faults are

not likely and the user should make their own

decision on earthing.

Slots are provided at the ends of the controller's base

for mounting. These will accept an M5 or M6 screw.

Under no circumstances should any other mounting

holes be drilled in the base as this could destroy the

controller. When mounting the controller take great

care that the heads of the mounting bolts cannot

short to any of the controller's internal busbars.

4QD series controller instructions.