Manufacturer's Safety Plan: Protective Measures And Equipment - Binder VDL Series Operating Manual

Material
The inner chamber is made of especially corrosion resistant stainless steel V4A (German material no.
1.4404, US equivalent AISI 316L) micro-polished. The rack holder and all of the chamber's vacuum con-
nections and valves are made of especially corrosion resistant stainless steel V4A (German material no.
1.4571, US equivalent AISI 316Ti). The housing is RAL 7035 powder-coated. All corners and edges of
the housing are also completely coated. When operating the chamber at temperatures above 150 °C /
302 °F, the impact of the oxygen in the air may cause discoloration of the metallic surfaces (yellowish-
brown or blue) by natural oxidation processes. These colorations are harmless and will in no way impair
the function or quality of the chamber.
The chambers are jacket-heated. The preheating chamber technique ensures a completely homogene-
ous jacket temperature, ensuring uniform heat transfer into the inner chamber. The low-loss heat transfer
to the material uses the aluminum vacuum expansion racks (or optionally available in stainless steel). The
elastic-mounted safety glass window reliably compensates any overpressure or explosions that may oc-
cur. The laminated safety glass pane ensures proven and effective splinter protection in the event of an
implosion.
The chambers provide a universal connection for inert gas / ambient air, a compressed air connection for
sweeping the electrical installation area and the controller housing, and a measuring connection serving
to connect a measuring access port.
All installable items, such as racks and rack holders, can be easily removed. The completely smooth in-
ner chamber with its rounded corners and internally welded seams is easy to clean.
The minimum working temperature of the vacuum drying oven is approx. 10 °C / 18 °F above room tem-
perature. The maximum temperature is 110 °C / 230 °F.
Vacuum pumps with a suction capacity of 1 m
3.1

Manufacturer's safety plan: Protective measures and equipment

The following measures were taken on the manufacturer's side in order to prevent ignition and explo-
sions.
• Ignition source monitored via safety temperature limiter (TL) class 2
Only solvents with an auto-ignition temperature above 200 ° C may be entered into the chamber.
There is a safety margin of 20% of the minimum permissible auto-ignition temperature of 200 °C, re-
lated to the hottest point in the interior (where the heating is attached to the inner chamber). The max-
imum surface temperature of the inner chamber is 160 °C. Therefore, when operated correctly, the hot
surfaces are always below the auto-ignition temperature of permitted substances.
The safety temperature limiter (TL) serves to protect the vacuum drying oven, its environment and
loading material against exceeding the permitted temperature. It has a fixed switching threshold and
prevents exceeding the maximum surface temperature of the inner chamber of 160 °C in the event of
a fault. If this temperature is exceeded, the heater turns off. The TL protects the VDL vacuum drying
oven, its environment and the loading material against impermissible excess temperatures and pre-
vents exceeding the maximum surface temperature in case of a fault.
The safety temperature limiter (TL) provides mechanical temperature monitoring through an expansion
tank. If the permissible temperature is exceeded, the heating is switched off via a relay and an addi-
tional self-holding circuit is activated, which is only reset when the power plug is removed and recon-
nected. This prevents the heating from being automatically switched on again via the relay. When the
TL is triggered, an alarm message is displayed on the controller. An annual function check by the op-
erator is recommended, for this a controller test routine is provided (chap. 16.5).
The setpoint can only be set up to the maximum drying temperature of 110 °C / 230 °F.
Control technology ensures that there are no temperature overshoots when heating up.
The interior is hermetically sealed against the heating system. The heating elements are always below
the auto-ignition temperature.
VDL (E3.1) 06/2020
3 3
/h to 30 m /h are suitable for the VD vacuum drying oven.
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