Specifications

ISTCD Detector Personality Module (ISTCD DPM), Continued
The connections to the ISTCD DPM are shown in figure 2-13 below. The
connections are described below.
Connections
Figure 2-13: ISTCD DPM Connections and Board ID
Orange connectors to detectors: Each ISTCD DPM consist two
connections. Each connection is capable of interfacing to two pairs of
TCD elements (four total channels, 1 for reference and 3 for signal).
Wiring of the connectors to the ovens depends on the configuration.
• A large analytical oven can contain two independent sets of
beads (eight channels), and will utilize both connectors from an
ISTCD DPM. One will control the right side of the oven and the
other will control the left side.
• A small analytical oven contains only one set of beads (four
channels), and only requires one connector. With two small
ovens installed one connector will go to the right oven and one
will go to the left oven.
Intrinsic Safety Grounds: The intrinsically safe design of the ISTCD DPM
requires two ground connections to the chassis. These ground
connections must also terminate to two different terminals. The Maxum II
Modular Oven is shipped with these grounds connected correctly. Refer
to the Maxum II Explosion Protection Safety Standards Manual
(A5E02220442001) for more information on the safe use of intrinsically
safe circuitry in the Maxum II.
I
2
C Bus Connection: The white connector on the reverse side of the DPM
is used for connection to the I
2
C Bus on the PECM-DC.
A5E31405710001 2-21