HSD - HSF
HSD / HSF resistors are heat sink cooled, low-power resistors in compact aluminum housings.
The main resistive element wraps around a support core; HSD / HSF resistors are wirewound resistors. The choice of alloy for the active wire will differ according to the requirements. The insulating material used is silicone rubber plus mica. The silicone is UL-approved and can withstand temperatures of up to 220°C.
The terminals for HSD resistors are vertical, and the terminals for HSF resistors are almost horizontal.
Power ratings for HSD / HSF resistors range from 40 to 250 W when mounted on a heatsink of 80°C and the maximum working voltage is 1200 VAC.
The nominal power depends on heat sink temperature. Higher temperatures lead to linear derating.
The ingress protection ratings for HSD / HSF resistors are IP00/IP50.
HSD / HSF resistors usually serve as balancing resistors.