  We present our analysis of Chandra observations obtained when the soft X-ray
transient RX J170930.2-263927 (XTE J1709-267) returned to quiescence after an
outburst. Using the type I burst peak luminosity found by Cocchi et al. (1998)
and the value of N_H we derived from our spectral fits, the distance to RX
J170930.2-263927 can be constrained to 2.5-10 kpc. RX J170930.2-263927 is
probably associated with the low-metalicity Globular Cluster NGC 6293, which
has a tidal radius of 14.2 arcminutes, since the projected distance to the
centre of the cluster is approximately 25 parsec (9-10 arcminutes). If the
association is correct, RX J170930.2-263927 would be at ~8.5 kpc. We determined
that L_outburst / L_quiescence is approximately 10^5 for this outburst. If the
quiescent luminosity is caused by cooling of the neutron star core then
enhanced core cooling processes were at work implying a neutron star mass of
\~1.7-1.8 Msun. Combining our Chandra observations with archival ROSAT
observations we show that the source most likely exhibits periods of sustained
low-level accretion. Variable, low-level activity could provide an alternative
explanation for some of the sources in the recently proposed category of faint
soft X-ray transients. We found excess emission at ~0.6 keV. If such an excess
is a unique feature of ultracompact systems, as was recently proposed, RX
J170930.2-263927 must have a short orbital period as well. From the constraints
on the distance and the non-detection of the optical counterpart with m_V<20.5,
we conclude that this system must have a low-mass companion.
