Bruker NMR AV4 BSMS System, Руководство пользователя

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BSVT Concept
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13.3.2 MAS Probes with Tempered Bearing Gas (VTN / WVT)
Some MAS probes have no specific VT gas channel, instead they use the MAS bearing gas
for temperature regulation. In these cases, the BSVT can be configured for
External VT Gas
Supply , where the probe heating is enabled as long as there is enough pressure on the
bearing gas detected. The VT gas valve in the BSVT unit is closed in this operation mode.
Figure 13.4: External VT Gas Supply (e. g. MAS3 Bearing Gas)
13.4 Frequently Asked Questions
• What is the difference between a power channel and an accessory channel?
A power channel provides, in contrast to an accessory channel, a variable power, which
can be controlled (VT power). The basic BSVT configuration provides 2 power channels
and 2 accessory channels. BSVT configurations can be extended up to 4 power channels
and 5 accessory channels.
Both channel types have the 15 pin D-Sub connecter at the user side, but the accessory
channel is connected to the back panel of the NMR cabinet by a smaller RJ45 connecter.
The width of the power channel cable is quite higher than that of an accessory channel.
• What happens if a probe is connected to an accessory channel?
A probe can be connected via the appropriate VT adapter to any channel. However, if the
channel does not provide VT power then the VT temperature of the probe cannot be
controlled and stabilized. Nevertheless, the temperature measurements are transferred in
regular intervals to the BSVT unit and displayed within the Topspin GUI.
• What could be the reason for inoperable devices?
It can happen that a power device connected to a power channel cannot be operated and
is marked as inoperable in the Topspin GUI. Either a heater or sensor cable between VT
adapter and heating device (e. g. probe) is not connected. Or the device (VT adapter) has
been added while the BSVT was in operation. In that case, the BSVT stays in operation
mode (if there is no device removed that was involved in temperature regulation), the new
devices are integrated into the BSVT temperature control as soon as the temperature
regulation is switched off next time.