  The design of the permanent magnet system for the new Quantum
Electro-Mechanical Metrology Suite (QEMMS) is described. The QEMMS, developed
at the National Institute of Standards and Technology (NIST), consists of a
Kibble balance, a programmable Josephson voltage standard, and a quantum Hall
resistance standard. It will be used to measure masses up to $100\,\mathrm{g}$
with relative uncertainties below $2\times 10^{-8}$. The magnet system is based
on the design of the NIST-4 magnet system with significant changes to adopt to
a smaller Kibble balance and to overcome known practical limitations.
Analytical models are provided to describe the coil-current effect and model
the forces required to split the magnet in two parts to install the coil. Both
models are compared to simulation results obtained with finite element analysis
and measurement results. Other aspects, such as the coil design and flatness of
$Bl$ profile are considered.
