The Q33B is a Mitsubishi MELSEC-Q series CPU base unit — the backplane that carries the CPU and up to three I/O or special-function modules. It draws 0.11 A from the 5 VDC rail on the power supply unit, so when you're sizing the system power budget, that's the load this base adds before any module current. Mounting uses M4 screws through the four corner holes (or the optional DIN-rail adapter Q6 DIN 3, sold separately). The footprint is 189 mm wide by 98 mm tall by 44.1 mm deep — compact enough for a standard cabinet backplate, but the 189 mm width means it won't fit a narrow sub-panel without checking clearances first.
Mitsubishi Q33B CPU Base Unit, 3 I/O Slots, 0.11 A at 5 VDC
MPNQ33B
Mitsubishi MELSEC-Q series CPU base unit, Q33B, 3 I/O unit slots, 0.11 A at 5 VDC, 189 x 98 x 44.1 mm.
$102.00Ref. price · indicative, final on quote
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Jul 2026
Specifications
| Parameter | Value |
|---|---|
| Mass | 0.21 kg |
| Depth | 44.1 mm |
| Width | 189 mm |
| Height | 98 mm |
| Applicable unit | MELSEC-Q series unit |
| Mounting hole size | M4 screw hole or f 4.5 hole (for M4 screw) |
| Applicable power supply unit | MELSEC-Q series power supply unit |
| Number of input (output units) | 3 |
| DC 5 v internal current consumption | 0.11 A |
| DIN rail mounting adapter type name | Q6 DIN 3 (sold separately) |
Product details
Frequently asked questions
What are the key dimensions of the Q33B?
Width is 189 mm, height is 98 mm, depth is 44.1 mm. The mounting holes accept M4 screws (or a 4.5 mm hole for M4). Mass is 0.21 kg.
MPN
Q33B